[0001] The invention relates to certain novel tricyclic benzo fused compounds, more particularly
to certain hexahydropyrrolo[1,2-a]quinoline, hexahydro-1H-pyrido-[1,2-a]quinoline,
hexahydrobenzo[e]indene and octahydrophenanthrene compounds of the formula

and pharmaceutically acceptable cationic and acid addition salts thereof, useful as
CNS agents, especially as analgesic and antiemetic agents for use in mammals, including
man; methods for their use, pharmaceutical compositions containing them and intermediates
therefor.
[0002] Despite the current availability of a number of analgesic agents, the search for
new and improved agents continues, thus pointing to the lack of an agent useful for
the control of broad levels of pain and accompanied by a minimum of side-effects.
The most commonly used agent, aspirin, is of no practical value for the control of
severe pain and is known to exhibit various undesirable side-effects. Other, more
potent analgesics such as d-propoxyphene, codeine, and morphine, possess addictive
liability. The need for improved and potent analgesics is, therefore, evident.
[0003] U.S. 4,188,495 discloses analgesic 1,9-dihydroxy-octahydrophenanthrenes, 1-hydroxyoctahydro-phenanthren-9-ones
and derivatives thereof which are prepared from intermediates of the formula

where M
a is CH
2, R
a and R
b are certain alkyl and aralkyl groups and R
c and.Za have many of the values given herein for R
1 and Z, respectively. ,
[0004] U.S. 4,260,764 discloses compounds of the above formula wherein M
a is NR
d where R
d is H or certain alkyl, aralkyl, carboxy substituted alkyl or acyl groups, and R
a, R
b, R
c and Z
a are as defined above.
[0005] U.S. patent no. 4,473,704 discloses various substituted dodecahydrotriphenylenes,
decahydro-1H-cyclopenta[1]phenanthrenes, decahydro-1H-pyrido[1,2-f]phenanthridines
and decahydropyrro-[1,2-f]-phenanthridines having activity as CNS agents.
[0006] The nomenclature employed herein is based on Rigaudy and Klesney, I.U.P.A.C. Nomenclature
of Organic Chemistry- 1979 Edition, Permangon Press, New York, including the use of
R and S to designate absolute stereochemistry and R* and S* to designate relative
stereochemistry. Formulae showing dotted and heavy bonds are generally intended to
specify relative stereochemistry, unless otherwise specified in the text.
[0007] It has now been found that certain hexahydropyrrolo[1,2-a]quinoline, hexahydro-1H-pyrido[1,2-a]-quinoline,
hexahydrobenz[e]indene and octahydrophenanthrene compounds are useful in mammals as
tranquillizers, anticonvulsants, diuretics, antidiarrheals, antitussives and as agents
for treatment of glaucoma. They are particularly effective in mammals, including man,
as analgesics and as agents for treatment and prevention of emesis and nausea, especially
that induced by antineoplastic drugs. Said invention compounds, which are nonnarcotic
and free of addiction liability, are of the formula

and pharmaceutically acceptable cationic and acid addition salts thereof, wherein
n is 1 and t is 1 or 2, M is CH or N, R
1 is H or (C
1-C
5)-alkanoyl,
Q is CO2R4 CH2(OR7), CONH2 or Q and OR1 are taken together to form

where
R8 is H, OH or (C1―C4) alkoxy;
R4 is H, (C1―C4)alkyl or benzyl;
R7 is H or (C2-C4)alkanoyl;
Z is (C5―C13)alkyl, (C5―C13)alkoxy, (C5―C13)alkoxyalkyl, (C9―C14)phenylalkyl, or (C9―C14)phenyl-alkoxy, wherein said phenyl groups are optionally substituted by chloro or
fluoro; or a pharmaceutically acceptable salt thereof.
[0008] Here and elsewhere in this application, the bracketed ranges of carbon atoms are
intended to encompass the range of carbon atoms of the entire group which follows.
For example (C
1―C
5)alkanoyl encompasses HCO- to C
4H
9CO―, while (C
9―C
14)phenylalkyl encompasses (C
6H
5)C
3H
6― to (C
6H
5)C
8H
16―.
[0009] Compounds of the present invention having particular utility as intermediates are
of the formulae

where
t and M are as defined above, the broken line is a bond or no bond, R15 is H, (C,-C4)alkyl acetyl or benzyl; when M is N, R16 and R17 are each hydrogen or taken together they form =0 (a carbonyl oxygen atom), and when
M is CH, R16 and R17 are each H;
Q, is COOR4; and
Z1 is (C1―C13)alkoxy, (C5―C13)alkyl, (C5―C13)alkoxyalkyl, (C9―C14)phenylalkyl or (C9―C14)phenyl-alkoxy.
[0010] Particularly preferred compounds of formula (I) are those wherein:
R, is H or acetyl,
n is 1, .
Q is COOR4, especially those where R4 is H, CH3 or C2H5; CH20R7, especially where R7 is H or acetyl; or CONH2; -
Z is (C5―13)alkyl, especially C(CH3)2(CH2)5CH3; (C5―C13)alkoxy, especially OCH(CH3)(CH2)4CH3; (C5―13)-alkoxyalkyl, (C9―C14)phenylalkyl, or (C9―C14)phenylalkoxy, especially OCH(CH3)(CH2)3C6H5. A more especially preferred value of Z is 5-phenyl-2-pentyloxy and 5-phenyl-2S-pentyloxy,
i.e.

is most preferred.
[0011] Particularly preferred intermediates of formula (II) and (III) are those wherein
R
16 and R
17 are each hydrogen, R
15 is H, CH
3 acetyl or benzyl; and Z
1 is OH, benzyloxy, methoxy or one of the particularly preferred values of Z, above.
[0012] Particularly preferred compounds of formula (I) wherein M is N are those having the
absolute or relative stereochemistry specified in the formula

[0013] Particularly preferred compounds of formula (I) wherein M is CH are those having
the absolute or relative stereochemistry specified in the formula

[0014] The ring systems and numbering used herein for the compounds of the present invention
are as follows:

[0015] Thus the compounds of formula (V) and (VI) are named as follows:
(V), t=1: 1,2,3,3aS,4,5R-hexahydro-5-[(CH2)nQ-substituent]-6-(OR1-substituent)-8-(Z-substituent)-pyrrolo[1,2-a]quinoline;
(V), t=2: 2,3,4,4aS,5,6R-hexahydro-6-[(CH2)nQ-substituent]-7-(OR1-substituent)-9-(Z-substituent)-1H-pyrido[1,2-a]quinoline;
(VI), t=1: 2,3,3aS,4,5,9bR-hexahydro-5-[(CH2)2Q-substituent]-6-(OR1-substituent)-8-(Z-substituent)-1H-benz[e]indene; and
(VI), t=2: 1,2,3,4,4aS,5,6,lObR-octahydro-6-[(CH2)nQ-substituent]-7-(OR1-substituent)-9-(Z-substituent)phenanthrene.
[0016] Likewise, the compounds of (II) are named as cyclic mono- or diketones having the
above ring systems and numbering, the compounds of formula (III) are named as lactones
of the corresponding compounds of formula (I) where R, is H, n is 1 and Q is COOH
or the corresponding unsaturated carboxylic acid.
[0017] Also included in this invention are pharmaceutically acceptable cationic and acid
addition salts of the compounds of formula (I). By pharmaceutically acceptable cationic
salts of the compounds of the invention is meant the salts of those compounds of formula
(I) where Q is a carboxylic acid group, said salts are formed by neutralization of
the carboxylic acid by bases of pharmaceutically acceptable metals, ammonia and amines.
Examples of such metals are sodium, potassium, calcium and magnesium. Examples of
such amines are ethanolamine and N-methylglucamine.
[0018] By the term pharmaceutically acceptable acid addition salts is meant the addition
salts formed between those compounds of formula (I) having one or more basic nitrogen
atoms in substituents M, R
i, Q or Z, and a pharmaceutically acceptable acid. Examples of such acids are acetic,
benzoic, hydrobromic, hydrochloric, citric, sulfosalicylic, tartaric, glycolic, malonic,
maleic, fumaric, malic, 2-hydroxy-3-naphthoic, pamoic, salicylic, phthalic, succinic,
gluconic, mandelic, lactic, sulfuric, phosphoric, nitric and methanesulfonic acids.
Of course, when more than one basic nitrogen atom is present in the free base of formula
(I), mono-, di- or higher addition salts may be obtained by employing one, two or
more equivalents of acid to form the desired acid addition salt.
[0019] Compounds having the formulae (I), (III), (V) and (VI), above, contain asymmetric
centers at the carbon sharing the ring juncture with M, at the carbon bearing ―(CH
2)
nQ and M when it is CH. There may be additional asymmetric centers in the substituents
Q, R
i and Z. The present invention includes the racemates of formula (I), the diastereomeric
mixtures, pure enantiomers and diastereomers thereof. The utility of the racemic mixtures,
the diastereomeric mixtures, as well as of the pure enantiomers and diastereomers
is determined by the biological evaluations described below.
[0020] As mentioned above, the compounds of the invention are particularly useful as analgesics,
and as antiemetic and antinausea agents for use in mammals, including man.
[0021] Also provided are pharmaceutical compositions for use as analgesics, as well as those
suitable for use in prevention and treatment of nausea, comprising an effective amount
of compound of the invention and a pharmaceutically acceptable carrier.
[0022] Methods which can be employed to provide the valuable intermediates of formulae (IX),
(IV) and (III) and their conversion to the therapeutically active compounds of formula
(I) where M is N or CH and n is 1, are outlined in Flow Chart A.

[0023] The enantiomeric or racemic starting materials of formula (VIII) wherein t, M, R,
S and Z, are as previously defined and R
15 is preferably benzyl or methyl are cyclized under dehydrating conditions to form
the corresponding tricyclic ketones of formula (IX). In a typical reaction of this
type the compound (VIII) is treated with a mixture of acetic acid/acetic anhydride
or trifluoroacetic acid/trifluoroacetic anhydride in molar excess, at a temperature
of from about 0° to 100°C. until the cyclization is substantially complete, which
usually requires from a few minutes up to several hours. The volatiles are then evaporated
under reduced pressure, the product isolated by standard extraction methods and purified
if desired by crystallization or by chromatographic methods.
[0024] In the second step of this reaction sequence the ketone of formula (IX) is reacted
under Reformatsky reaction conditions with an alpha-haloester in the presence of zinc
metal, but preferably with a lithio acetic acid ester reagent of the formula LiCH
2Q
1, where Q, is COOR
4 and R
4 is alkyl having from one to four carbon atoms. For an extensive review of the Reformatsky
reaction, see, e.g. Rathke, Organic Reactions, 22 423-460 (1975).
[0025] When the preferred lithio reagents, LiCH
2Q
1, are employed to prepare the intermediates of formula (IV), they may be prepared
by any of several methods known in the art; see, for example, Fieser, "Reagents for
Organic Chemistry", Wiley-Interscience, New York, Vol. 3,1972. However, a preferred
method, exemplified herein, employs a lithium dialkylamide and an acetic acid ester
in reaction inert solvent. A particularly preferred lithium dialkylamide is lithium
dicyclohexylamide. The latter compound is prepared, for example, from equimolar amounts
of n-butyl lithium and dicyclohexylamine in reaction inert solvent. In a typical reaction
the two reagents are contacted under anhydrous conditions and in the presence of an
inert atmosphere, e.g., nitrogen, at -80 to -70°C. in reaction inert solvent and to
the resulting slurry is added an equimolar amount of reagent of formula CH
3Q, at the same temperature. The resulting lithio reagent, LiCH
2Q
l is then reacted immediately with the intermediate ketone (IX) in reaction inert solvent
also at a temperature of from about -80 to -70°C. The reaction is ordinarily completed
in from about one to ten hours, after which the reaction mixture is quenched by addition
of an equivalent amount of weak acid, e.g., acetic acid, to decompose the lithium
sa.lt of the desired product. The product is then isolated by standard methods and
purified, if desired, as described above. Examples of the reaction inert solvents
which may be employed and preferred such solvents are those mentioned above for the
reaction employing haloester reagents.
[0026] The 5,5- (or 6,6-)hydroxy-CH
2Q
1-disubstituted compounds of formula (IV), obtained as described above, are then subjected
to dehydration to provide compounds of the formula (X) followed by hydrogenation to
give compounds of the formula (Xi) and removal of hydroxy protecting methyl or benzyl
groups, R
is, to provide compounds offormula (XII). The hydrogenation of compounds offormula (X)
where Q, is COOR
4 is ordinarily carried out by means of hydrogen in the presence of a noble metal catalyst.
Examples of noble metals which may be employed are nickel, palladium, platinum and
rhodium. The catalyst is ordinarily employed in catalytic amounts, e.g., from about
0.01 to 10 weight-percent and preferably from about 0.1 to 2.5 weight-percent, based
on the compound of formula (X). It is often convenient to suspend the catalyst on
an inert support, a particularly preferred catalyst is palladium suspended on an inert
support such as carbon.
[0027] One convenient method of carrying out this transformation is to stir or shake a solution
of the compound of formula (X) under an atmosphere of hydrogen in the presence of
one of the above noble metal catalysts. Suitable solvents for this hydrogenolysis
reaction are those which substantially dissolve the starting compound of the formula
(X) but which do not themselves suffer hydrogenation or hydrogenolysis. Examples of
such solvents include the lower alkanols such as methanol, ethanol and isopropanol;
ethers such as diethyl ether, tetrahydrofuran, dioxan and 1,2-dimethoxyethane; low
molecular weight esters such as ethyl acetate and butyl acetate; tertiary amides such
as N,N-dimethylformamide, N,N-dimethylacetamide and N-methylpyrrolidone; and mixtures
thereof. Introduction of the hydrogen gas into the reaction medium is usually accomplished
by carrying out the reaction in a sealed vessel, containing the compound of formula
(X), the solvent, the catalyst and the hydrogen. The pressure inside the reaction
vessel can vary from about 1 to about 100 bar. The preferred pressure range, when
the atmosphere inside the reaction vessel is substantially pure hydrogen, is from
about 2 to about 5 bar. The hydrogenolysis is generally run at a temperature of from
about 0°C to about 60°C., and preferably from about 25°to about 50°C. Utilizing the
preferred temperature and pressure values, hydrogenolysis generally takes place in
a few hours, e.g., from about 2 hours to about 24 hours.
[0028] The product is then isolated by standard methods known in the art, e.g., filtration
to remove the catalyst and evaporation of solvent or partitioning between water and
a water immiscible solvent and evaporation of the dried extract.
[0029] When the starting compound employed in the hydrogenation is of formula (X) wherein
R,
5 is hydrogen or benzyl and Q, is COOR
4, the product obtained is ordinarily a mixture of the corresponding carboxylic acid
or ester of formula (XII) and the lactone of formula (111) formed by elimination of
the elements of R
40H from (XII), (XI) or (X) where R
15 = H. The mixture thus obtained may be used as is or may be separated by well known
methods, e.g., by crystallization and/or chromatography on silica gel.
[0030] Of course, when the starting compound for the hydrogenation is of formula (X) wherein
R
15 is alkyl, as defined above and Q, is COOR
4, the only product obtained is the corresponding OR'
5-substituted derivative of formula (XI). Removal of the hydroxy protecting group R
15, by methods known in the art for cleaving ethers e.g., by means of HBr/acetic acid,
then affords the desired compound of (XII) or its mixture with lactone (111).
[0031] The products of formulae (XII, Q, = CO
2R
4) and (111), as well as mixtures thereof, are useful intermediates for production
of the corresponding hydroxy compounds of formula (XV) by means of known reducing
agents, e.g., hydrides such as lithium aluminum hydride or lithium borohydride, aluminum
borohydride, borane, aluminum hydride and lithium triethylborohydride and by catalytic
hydrogenation over noble metal catalysts. Preferred reducing agents are the above
hydrides and especially preferred is lithium aluminum hydride for reasons of economy
and efficiency. The reduction is carried out under anhydrous conditions and in the
presence of a suitable reaction inert solvent e.g., ethyl ether, tetrahydrofuran,
1,2-dimethoxyethane and diethyleneglycol dimethylether. Typically, the compound of
formula (XII, Q, = C0
2R
4), the lactone (III) or mixture thereof dissolved in one of the above reaction inert
solvents is added to a solution of an approximately equimolar amount of hydride, e.g.,
lithium aluminum hydride, in the same solvent and the mixture maintained at a temperature
of from about -50 to 50°C., and preferably from about 0 to 30°C. Under these conditions
the reduction is substantially complete in from about 2 to 24 hours, after which the
excess reducing agent is quenched, e.g., by cautious addition of wet solvent or ethyl
acetate and the product isolated by known techniques, e.g., washing the reaction mixture
with water and evaporation of the dried organic phase. Purification, if desired, is
carried out, e.g., by recrystallization or column chromatography.
[0032] The lactones (III) wherein the broken line is no bond are also useful as intermediates
for production of the corresponding lactols of formula (XXVI) by means of reagents
and conditions known to selectively reduce the lactone carbonyl group to a carbinol
without ring cleavage. A preferred such reagent is diisobutylaluminum hydride (DIBALH).
In a typical reaction, the saturated lactone (III) is dissolved in a reaction inert
solvent, such as an aromatic hydrocarbon solvent, preferably toluene, the solution
is cooled to a temperature of from about -90 to -50°C., preferably about -80° to -60°C.,
under anhydrous conditions and in the presence of an inert atmosphere such as nitrogen
or argon. An equimolar amount of DIBALH is then added slowly while maintaining the
mixture within the preferred temperature range. After the addition is complete, the
reaction is allowed to proceed under these conditions until substantially complete,
which ordinarily requires from about one to ten hours. The reaction mixture is then
quenched, for example, by addition of methanol, then allowed to warm to room temperature.
The desired lactol (XXVI) is then isolated, e.g., by washing with water, drying and
evaporation of solvent.

[0033] Reaction of the lactols of formula (XXVI) with alcohols of formula (R
s)'OH, where (R
8)' is alkyl having from one to four carbon atoms, under acidic conditions known to
convert lactols (hemiacetals) to acetals provides the corresponding acetals. In a
typical reaction, the lactol is dissolved in a large excess, e.g., a solvent amount
of the alcohol of formula (R
8)'OH, dry hydrogen chloride or concentrated sulfuric acid added in from a catalytic
amount up to an amount equimolar to the lactol and the mixture maintained at a temperature
of from about 0°C. up to the boiling point of the alcohol, preferably room temperature,
until acetal formation is complete. The time required for completion is ordinarily
about 4―48 hours. After which the acetal is isolated by known methods, e.g., by pouring
into water, extracting with ether, drying the extracts and evaporation of solvent.
The product thus provided is ordinarily a mixture of the alpha- and beta-anomeric
acetals which can be separated, e.g., by chromatography on silica gel.
[0034] Flow Chart C, below outlines an alternative method for preparing.5-(2-hydroxyethyl)hexahydro-pyrrolo[1,2-a]quinoline
and 6-(2-hydroxyethyl)hexahydropyrido-[1,2-a]quinoline compounds of the formula (XXV),
(XV, M is N) or (I, n is 1, Q is CH
20H).
[0035] In the initial step of this reaction sequence the 3-oxoadipate diester or 3-oxopimelate
diester of formula (XVI), prepared by condensation of the half ester acid chloride
of succinic or glutaric acid with ethyl lithio-acetate in the presence of a condensing
agent, e.g., dicyclohexylcarbodiimide; is contacted with a 3-(OR,,-substituted)-5-Z
i-substituted-aniline offormula (XVII) under hydrogenation conditions. Typically the
reactants of formula (XVI) and (XVII) are combined in approximately equimolar amounts
in the presence of acetic acid and shaken with a catalytic amount of platinum at ambient
temperature under a hydrogen atmosphere until the reduction of the Schiff base formed
is complete. After removal of catalyst and evaporation of the bulk of the acetic acid,
the residue is added to refluxing HBr/acetic acid to affect cyclization and hydrolysis
to the acid of formula (XVIII) or the ketolactam (XIX). When the product is the acid
(XVIII), it is further cyclized under dehydration conditions to afford the corresponding
compound (XIX). In the, intermediates (XVIII) and (XIX) produced from starting anilines
(XVII) wherein R
15 is alkyl or benzyl.

and/or Z, is alkoxy or benzyloxy, the ether groups are cleaved by the treatment with
HBr/acetic acid, to give products wherein R,
5 and Z, are H and OH, respectively. When this is the case, it is ordinarily preferable
to complete the side chain, Z, by selective esterification, e.g., by reaction of intermediate
(XIX, R
1 = H, Z, = OH) with the appropriate side chain precursor of formula Z
2X where Z
2 plus an atom of oxygen forms Z, and X is a leaving group, e.g., Cl, Br, 1, CH
3SO
2O or 4-CH
3C
6H
4SO
2O. A preferred value of X is CH
3S0
20.
[0036] The remaining steps to form intermediates (XXI), (XXII), (XXIII), (XXIV) are carried
out as previously described for the corresponding steps depicted in Flow Chart A to
provide compounds of formulae (IV), (X), (XI), (XII) and (III). The final step, to
reduce to lactam-lactone (XXIV), is ordinarily carried out by hydride reduction, preferably
employing lithium aluminum hydride, by methods described above for reduction of lactones
(III).
[0037] One sequence available for the preparation of numerous starting compounds of formula
(VIII, M is CH) employs as a first stage the heating of cyclohexanone or cyclopentanone
with a suitable substituted phenyl Grignard in a high boiling, reaction inert solvent
to produce a compound of the formula

wherein t is as defined above, R
15 is methyl or benzyl and Z, is methoxy, benzyloxy, (C
5―C
13)alkyl, C
1―C
13)alkoxyalkyl, (C
9―C
14)phenylalkyl, or (C
9―C
14)phenylalkoxyalkyl. Condensation with alkyl acetate, dehydration, and hydrolysis of
intermediate ester produces unsaturated acids of the formulae

Equivalents such as malonate (decarboxylate to the acetate after hydrolysis) can be
substituted for the alkyl acetate. Lithium in liquid ammonia reduction of the former
yields the trans-form of the substituted acetic acid derivatives, while catalytic
hydrogenation of the latter under conditions detailed above yields the cis-form of
the acetic acid (with simultaneous debenzylation when R,
5 is benzyl). Finally, cyclization, debenzylation or 0-demethylation and alkylation
when Z is a phenolic ether derivative, yields tricyclic ketones of the respective
formulae

wherein n and Z are as hereinbefore defined.
[0038] Alternatively, suitable substituted aromatic aldehydes are condensed with nitromethane
to yield trans-1-(disubstituted phenyl)-2-nitroethylenes of the formula

wherein R
15 is as defined above and Z
2 is methoxy, benzyloxy or Z is as defined above. Condensation of the latter with butadiene
under Diehls-Alder conditions yields the corresponding 4-(substituted phenyl)-5-nitro-cyclohexene.
The Nef reaction converts the nitro compound to the unsaturated cyclohexanone derivative,
viz, 6-(disubstituted phenyl)-3-cyclohexen-1-one which is hydrogenated according to
methods detailed above (with simultaneous removal of benzyl, if present); demethylated
if methyl ether is present (with simultaneous dealkylation if Z2 is an alkoxy derivative);
and alkylated if Z is an alkoxy derivative to yield a ketone of the formula

wherein Z is as defined above. It will be noted that inversion occurs in such alkylation
reactions, e.g., 5-phenyl-2S-pentyl mesylate yields Z as 5-phenyl-2R-pentyloxy.
[0039] Corresponding tricyclic nitrogen analogs are conveniently prepared from 3,omega-dihalo
acids and disubstituted anilines, e.g.,

wherein t, R
15, Z, and Z
2 are as defined above, followed by cyclization, debenzylation or demethylation (accompanied
by dealkylation when Z, is an alkoxy derivative) and alkylation when Z is an alkoxy
derivative to yield pyrrolo/pyrido[1,2-a]quinolinones of the formula

[0040] Many of the anilines, aromatic halides or aromatic aldehydes required as starting
materials for the present syntheses are available commercially or their syntheses
are reported in the literature. When not otherwise available, the anilines required
for the present syntheses are prepared by methods previously set forth by Johnson,
U.S. Patent 4,260,764. The latter are converted to the corresponding aromatic bromides
and chlorides according to procedures set forth by Bigelow, Organic Syntheses I, pp.
135-137 (1941) and then reacted with magnesium to provide the required Grignard reagents.
While a variew of methods are available for the synthesis of the required aldehydes
they are also broadly available from the anilines of Johnson. The anilines are converted
to the corresponding nitriles by the method of Clarke and Read, Organic Syntheses
I, pp. 514-516 (1941). The nitriles are subjected to the Stephen reduction to yield
the aldehyde directly. Alternatively, the nltriles are hydrolyzed to acid, then converted
to acid chloride and hydrogenated under Rosemund conditions. Acid chlorides can also
be converted to the thiol ester and desulfurized to aldehydes according to Wolfram
et al., J. Am. Chem. Soc. 68, pp. 1455―1546. Alternatively, aldehydes are obtained
from the corresponding benzyl. aldehydes by oxidation in dimethylsulfoxide according
to Kornblum et al., J. Am. Chem. Soc. 81, pp. 4113―4114. The benzyl bromides are prepared
according to methods set forth in Althuis et al., U.S. Patent 4,188,495. Aldehydes
are also available by reaction of aromatic Grignard reagents with ethyl orthoformate.
[0041] When Z is (C
5―C
13)alkoxy, or (C
9―C
14)phenylalkoxy (the phenyl group optionally substituted with a chloro orfluoro), the
required halide or mesylate, if not available commercially, is readily obtained from
the corresponding alcohol using conditions standard in the chemical art. The alcohols
in turn are available commercially or by literature methods. For example primary alcohols
are available by hydride reduction of aldehydes, acids or esters, while secondary
alcohols are available by hydride reduction of ketones. All varieties of alcohols
are available by the hydration of olefins, or by the reaction of epoxides with Grignard
reagents. Furthermore, many halides suitable for the introduction of the sidechain
are available by direct halogenation of olefins or addition of hydrogen halides to
olefins.
[0042] When the optically active variant of one of the compounds of the present invention
is desired, resolution is accomplished by formation and separation of diastereomeric
salts derived from an optically active amine/acid with an acidic/basic intermediate
or end product according to methods well known in the chemical art. Alternatively,
alcohol intermediates are resolved by formation of diasteromeric esters, e.g. optically
active amine salts of hemiphthalate esters or are formed directly by use of optically
active reagents. It is preferred, however, to carry out the resolution at an early
stage in the process in order to avoid unnecessary processing of material which is
not desired.
[0043] The pharmaceutically acceptable acid addition salts of the present invention are
readily prepared by contacting the free base with the appropriate mineral or organic
acid in either aqueous solution or in a suitable organic solvent. The salt can then
be obtained by precipitation or by evaporation of the solvent. The pharmaceutically
acceptable acid addition salts of this invention include, but are not limited to,
those formed with hydrochloric, hydrobromic, nitric, phosphoric, sulfuric, benzenesulfonic,
citric, laurylsulfonic, fumaric, oxalic, maleic, methanesulfonic, tartaric, p-toluenesulfonic,
and succinic acid. With polybasic acids, the salt can include more than one mole of
base per mole of acid. However, the acid addition salts which are mole for mole are
preferred. If desired, these salts are isolated directly from reaction mixtures by
suitable modification of the isolation procedure, without isolation of the intermediate
free acid.
[0044] The pharmaceutically acceptable cationic salts of the compounds of the present invention
are readily prepared by reacting the acid forms with an appropriate base, usually
one equivalent, in a co-solvent. By the expression "pharmaceutically acceptable cationic
salts" is intended salts such as the alkali metal salts, e.g., sodium and potassium;
alkaline earth metal salts such as calcium and magnesium; aluminum salts; ammonium
salts; and salts with organic bases, e.g., amines such as benzathine (N,N'-dibenzylethylenediamine),
choline, diethanolamine, ethylenediamine, meglumine (N-methylglucamine), benethamine
(N-benzylphenethylamine), diethylamine, piperazine, and tromethamine (2-amino-2-hydroxymethyl-1,3-propanediol).
Typical bases employed in the preparation of these cationic salts are sodium hydroxide,
sodium methoxide, sodium ethoxide, sodium hydride, potassium methoxide, magnesium
hydroxide, calcium hydroxide, benzathine, choline, diethanolamine, ethylenediamine,
meglumine, benethamine, diethylamine, piperazine and tromethamine. The salt is isolated
by concentration to dryness or by addition of a non-solvent. In some cases, salts
can be prepared by mixing a solution of the acid with a solution of a different salt
of the cation (e.g., sodium ethylhexanoate, magnesium oleate), employing a solvent
in which the desired cationic salt precipitates, or can be otherwise isolated by concentration
and/or addition of a non-solvent. If desired, these salts are isolated directly from
reaction mixtures by suitable isolation procedures, without isolation of the intermediate
free acid.
[0045] Phenolic esters of compounds of formula (I) wherein R
1 is benzoyl, alkanoyl or -CO-(CH
2)p-NR
2R
3 are readily prepared by reacting formula (I) compounds wherein R
1 is hydrogen with benzoic acid, the appropriate alkanoic acid or acid of formula HOOC―(CH
2)
p-NR
2R
3 in the presence of a condensing agent such as dicyclohexylcarbodiimide. Alternatively,
they are prepared by reaction of the formula (I) (R,=H) compound with the appropriate
acid chloride or anhydride, e.g., benzoyl chloride, acetyl chloride or acetic anhydride,
in the presence of a base such as pyridine.
[0046] The presence of a basic group in the ester moiety (OR,) in the compounds of this
invention permits formation of acid-addition salts involving said basic group. When
the herein described basic esters are prepared via condensation of the appropriate
amino acid hydrochloride (or other acid addition salt) with the appropriate compound
of formula (I) in the presence of a condensing agent, the hydrochloride salt of the
basic ester is produced. Careful neutralization affords the free base. The free base
form can then be converted to other acid addition salts by known procedures.
[0047] The analgesic properties of the compounds of this invention are determined by tests
using thermal nociceptive stimuli, such as the mouse tail flick procedure, or chemical
nociceptive stimuli, such as measuring the ability of a compound to suppress phenyl
benzoquinone irritant-induced writhing in mice. These tests and others are described
below.
Tests Using Thermal Nociceptive Stimul.i
(a) Mouse Hot Plate Analgesic Testing .
[0048] The method used is mo.dified after Woolfe and MacDonald, J. Pharmacol. Exp. Ther.,
80, 300-307 (1944). A controlled heat stimulus is applied to the feet of mice on a
1/8" thick aluminum plate. A 250 watt reflector infrared heat lamp is placed_ under
the bottom of the aluminum plate. A thermal regulator, connected to thermistors on
the plate surface, programs the heat lamp to maintain a constant temperature .of 57°C.
Each mouse is dropped into a glass cylinder (61/2" diameter) resting on the hot plate,
and timing is begun when the animal's feet touch the plate. At 0.5 and 2 hours after
treatment with the test compound the mouse is observed for the first "flicking" movements
of one or both hind feet, or until 10 seconds elapse without such movements. Morphine
has an MPE
SO = 4-5.6 mg.kg. (s.c.).
[0049] The physician will determine the dosage which will be most suitable for an individual
patient and it will vary with the age, weight and response of the particular patient
and the route of administration. Generally, 'however, the initial analgesic dosage
in adults is from 0.01 to 500 mg. per day in single or divided doses. In many instances,
it is not necessary to exceed 100 mg. daily. The favored oral dosage range is from
0.01 to about 300 mg./day; the preferred range is from 0.10 to about 50 mg./day. The
favored parenteral dose is from 0.01 to 100 mg./day; the preferred range is from 0.01
to 20 mg./day.
[0050] The use of these compounds for the treatment of glaucoma is believed to be due to
their ability to reduce intraocular pressure. Their effects on intraocular pressure
are determined by tests on dogs. The test drug is instilled into the eye of a dog
in the form of a solution or is administered systemically at various periods of time
after which the eye is anesthetized by instillation oftetracaine hydrochloride, 1/2%,
2 drops. Afew minutes after this local anesthesia, introocular pressure readings are
taken with a Schiotz mechanical tonometer and after fluorescein dye is'administered,
with a Holberg hand application tonometer. The test drug is conveniently used in a
solution such as the following: test drug (1 mg.), ethanol (0.05 ml.), Tween 80 (polyoxyalkylene
derivative of sorbitan monooleate, available from Atlas Powder Co., Wilmington, Del.
19899; 50 mg.) and saline (to make 1 ml.), or in a more concentrated solution wherein
the ingredients are present in proportions of 10 mg., 0.10 mi., 100 mg. and 1 ml.,
respectively. Alternatively the compounds of the present invention are tested for
their ability to reduce intraocular pressure in normal rabbits according to the method
of Elsohly et al., J. Clin. Pharmacol. 21, pp. 472S―478S (1981). For human use, concentrations
of drug from 0.01 mg./kg. to 10 mg.kg. are useful.
[0051] Their activity as diuretic agents is determined by the procedure of Lipschitz etal.,
J. Pharmacol., 79, 97 (1943) which utilizes rats as the test animals. The dosage range
for this use is the same as that noted above with respect to their use as analgesic
agents.
[0052] The antiemetic properties of the compounds of the present invention are determined
in unanesthetized unrestrained cats according to the procedure described by McCarthy
and Borison, J. Clin. Pharmacol., 21, 308―37S (1981). The dosage ranges for this utility
is also the same as that noted above with respect to their analgesic utility.
[0053] This invention also provides pharmaceutical compositions, including unit dosage forms,
valuable for the use of the herein described compounds as analgesics and other utilities
disclosed herein. The dosage form may be given in single or multiple doses, as previously
noted, to achieve the daily dosage effective for a particular utility.
[0054] The compounds (drugs) described herein can be formulated for administration in solid
or liquid form for oral or parenteral administration. Capsules containing drugs of
this invention; i.e.; compounds of formulae (I), (V) or (VI), are prepared by mixing
one part by weight of drug with nine parts of excipient such as starch or milk sugar
and then loading the mixture into telescoping gelatin capsules such that each capsule
contains 100 parts of the mixture. Tablets containing the same compounds are prepared
by compounding suitable mixtures of drug and standard ingredients used in preparing
tablets, such as starch, binders and lubricants, such that each tablet contains from
0.01 to 100 mg. of drug per tablet.
[0055] Suspensions and solutions of these drugs of formulae (I), (V) or (VI) are generally
prepared just prior to use in order to avoid problems of stability of the drug (e.g.
oxidation) or of suspensions or solution (e.g. precipitation) of the drug upon storage.
Compositions suitable for such are generally dry solid compositions which are reconstituted
for injectable administration.
[0056] The present invention is illustrated by the following examples. However, it should
be understood that the invention is not limited to the specific details of these examples.
[0057] When compounds containing more than one asymmetric center contains a center of unspecified
absolute or relative stereochemistry (e.g. 5-phenyl-2-pentyl) it will be understood
by those skilled in the art that the product is a mixture of two diastereoisomers
or two racemates, respectively, usually in a ratio of about 1:1. _
Example 1
01-Ethyl O7-Methyl 3-Oxoheptandioate
[0058] A five liter round bottom flask was fitted with a mechanical stirrer, thermometer
and a one liter addition funnel. The addition funnel was in turn fitted with a septum
into which was introduced a nitrogen line, an equalizing line and a liquid reagent
inlet line. The equalizing line was further connected with tubing to a straight vacuum
adapter and this adapter was fitted between the addition funnel and the five liter
flask. The flask was charged with nitrogen then with 976 ml. (2.05 moles = 2.25 equiv.)
n-butyllithium in 800 ml. anhydrous tetrahydrofuran (THF) and the mixture was cooled
to -78°C. in a dry ice/acetone bath. To this was added 408 ml. (2.05 moles) of dicyclohexylamine
in 375 ml. THF dropwise over 45 minutes (temperature kept below -67°C.). After equilibrating
to -78°C., 201 ml. (2.05 moles) of freshly distilled ethyl acetate in 100 ml. THF
was added dropwise over 45 minutes (below -67°C.). After addition, the mixture was
allowed to stir at -78°C. for 15 minutes. After 15 minutes 150 g. (0.91 moles) of
methyl 4-(chloroformyl)butyrate dissolved in 200 mi. THF was added dropwise over 30
minutes (below -70°C.). The mixture was then stirred one hour at -78°C., after which
231 ml. (2.05 moles) of glacial acetic acid was added dropwise over 25 minutes. After
addition was complete the dry ice/acetone bath was removed and the reaction mixture
was allowed to warm to 0°C. After diluting with one liter of ethyl ether, the precipitated
inorganic material was filtered and washed well with ether. The combined organic solvents
were evaporated in vacuo. The residue was partitioned between Et
20/H
20 (1000 ml. of each) and separated. The ether layer was washed with 2 x 500 ml., 0.5N
hydrochloric acid (some solids precipitated with the first wash and were filtered;
no precipitate was observed with the second wash). The organic layer was washed with
500 ml. H
20, 500 ml. saturated sodium bicarbonate solution, 500 ml. H
20, 500 ml. brine, and finally dried over anhydrous magnesium sulfate.
[0059] The ether was filtered and the solvent evaporated in vacuo to yield 108.5 g. (55.1%)
of 3-oxopimelic acid, ethyl, methyl diester as a gold colored mobile liquid;'H-NMR
(CDCI
3) ppm (delta): 1.25 (t, CH
zCH
20), 1.7-2.7 (m, ―CH
2CH
2CH
2―), 3.4 (s, ―C―CH
2C―), 3.6 (s, CH
3O―), 4.1 (q, CH
3CHO-). Mass spectrum (m/e): 216 (M
+).
Example 2
01-Ethyl O6-Methyl 3-Oxohexandioate
[0060] When the procedure of Example 1 was repeated, but using methyl 3-(chloroformyl)propionate
in place of methyl 4-(chloroformyl)butyrate the crude title compound was obtained
in quantitative yield as a light orange oil which was distilled to afford the pure
diester, B.P. 125-135°C. (1.5-2.5 mm.) in 48% yield. 'H-NMR (CDC'
3) ppm (delta): 1.28 (t, 3H, J=7Hz), 2.06-3.13 (m, 4H), 3.47 (s, 2H), 3.70 (s, 3H),
4.16 (q, 2H, J=7Hz).
Example 3
d/-6,8-Dihydroxy-3a,4-dihydro-(2H,3H)-pyrrolo[1,2-a]quinolin-1,5-dione
[0061] In a pressure bottle were combined 48.5 g. (0.32 mole) 3,5-dimethoxyaniline, 1.4
g. platinum dioxide, 64.0 g. (0.32 mole) O
1-ethyl 0
6-methyl 3-oxohexandioate and 140 ml. glacial acetic acid and shaken under hydrogen
at 40―50 psi (2.8―3.5 bar) for 90 hours. The mixture was filtered through diatomaceous
earth, washing with 3 x 40 ml. acetic acid. The combined filtrate and washings were
evaporated in vacuo to obtain about 125 ml. of residue.
[0062] In a separate flask 490 ml. 48% hydrobromic acid and 270 ml. acetic acid were heated
to reflux with stirring. To this was added dropwise the ~125 ml. residue from above.
The addition required about 30 minutes, during which gas evolution was vigorous. The
resulting mixture was refluxed for an additional 30 minutes. The flask was fitted
with a distillation head and condensor and 700 ml. of distillate was collected over
three hours. The residual mixture was poured onto a liter of crushed ice and the resulting
red solids collected by filtration (62 g.). Extraction of the filtrate with ethyl
acetate (2 liters), drying and evaporation of solvent gave an additional 7 g. of red
solid. The combined red solids were dissolved in 3.5 liters of boiling methanol. Upon
cooling and filtration of precipitate, 25.4 g. of light orange solids was obtained.
Evaporation of the mother liquor to one liter and cooling affords an additional 10.2
g. orange solids. A third crop was collected after evaporation of the mother liquor
to ~250 ml. (5.7 g.). Total yield, 41.3 g. (55.4%), M.P. 250° (decomp.).'H-NMR [C(D
3)
2SO] ppm (delta): 1.5-2.3 (m, 2H), 2.4-3.8 (m, 4H), 4.0-4.7 (m, 1H), 6.0 (d, 1H, J=2.5Hz),
7.6 (d, 1H, J=2.5Hz), 9.3 (s, 1H), 10.4 (s, 1 H). Infrared spectrum (KBr) microns:
2.9 (OH), 3.5 (OH), 5.95 (CO), 6.1 (CO).

Example 4
d/4a,5-Dihydro-7,9-dihydroxy-(2H,3H,4H)-pyrido[1,2-a]quinoline-1,6-dione
[0063] A. A mixture of 41.0 g. (0.19 mole) 0'-ethyl 0'-methyl 3-oxoheptandioate, 1.0 g.
PtO
2 catalyst, 29.1 g. (0.19 mole) 3,5-dimethoxyaniline and 80 ml. glacial acetic acid
was hydrogenated at 50 psi (3.5 bar) for 36 hours. The catalyst was removed by filtration,
washing with acetic acid and the filtrate evaporated in vacuo to 100 ml.
[0064] This was added dropwise under nitrogen, to a refluxing mixture of 360 ml. 48% hydrobromic
acid and 200 ml. glacial acetic acid. The resulting mixture was heated at reflux for
30 minutes after the addition was completed. The mixture was concentrated, under a
nitrogen stream, by distillation, 500 mi. of distillate being collected overthree
hours. The residue was cooled to room temperature, poured onto 500 ml. ice and extracted
with 4 x 500 ml. ethyl acetate. The extracts were dried (MgS0
4) and solvent evaporated in vacuo to yield 33 g. (65.5%) of 4-[2,3-dihydro-5,7-dihydroxy-(1H)-quinolin-4-one-2-yl]butyric
acid as a light brown gum.
1H―NMR [(CD
3)
2SO] ppm (delta): 1.6―3.55 (m, 10H), 5.58 and 5.75 (2H, split doublets), 6.75 (1H,
OH), 10.2 (1H, OH), 12.75 (1H, COOH). Mass spectrum (m/e): 265 M
+. Infrared (KBr) 5.89 microns (GOOH).

[0065] B. A mixture of 26 g. (0.098 mole) 4-[2,3-dihydro-5,7-dihydroxy-(1H)-quinolin-4-one-2-yl]butyric
acid and 260 mi. methanesulfonic acid was heated under a nitrogen atmosphere at 140°C.
for two hours. The reaction mixture was cooled to room temperature and poured onto
1000 ml. ice. To this was added 4 liters ethyl acetate, 1 liter water, 250 g. sodium
chloride and the resulting mixture stirred at room temperature overnight. The layers
were separated, the aqueous phase extracted with 4 x.500 ml. ethyl acetate and the
combined organic layers washed with saturated sodium bicarbonate solution until the
pH was 7 and no effervescence was observed. The extract was then washed with water
(1000 ml.), brine (1000 ml.) and dried (MgS0
4). The solvent was evaporated in vacuo, the residue redissolved in a small amount
of hot ethyl acetate, diluted with ethyl ether and cooled to 0°C. The precipitated
solid was collected by filtration and dried in vacuo to afford 9.4 g. (38.8%) of the
title compound, M.P. 259-268°C. (decomp.). 'H-NMR [(CD
3)
2SO] ppm (delta): 1.75-3.25 (m, 11H), 6.1 and 6.95 (2H, split doublets, meta aryl).
Mass spectrum (m/e): 247 M
+.

Example 5
Diastereomers of 6-Hydroxy-8-(5-phenyl-2-pentyloxy)-3a,4-dihydro(2H,3H)pyrrolo[1,2-a]guinolin-1,5-dione
[0066] Under anhydrous conditions and in a nitrogen atmosphere, 70 g. (0.30 mole) 6,8-dihydroxy-3a,4-dihydro-(2H,3H)-pyrrolo[1,2-a]quinolin-1,5-dione
was dissolved in 750 ml. dimethylformamide by warming to 60°C. To the resulting deep
red solution was added 51.6 g. (0.675 mole) potassium carbonate. The mixture was heated
to 70°C., a solution of 2-methylsulfonyloxy-5-phenylpentane in 250 mi. dimethylformamide
was added in a fast stream, and heated at 75―80°C. for 12 hours. Additional portions
of 2-methylsulfonyloxy-5-phenylpentane (5.3 g.) and potassium carbonate (3.8 g.) and
heating continued at 75―80°C. for two hours. The mixture was poured over a mixture
(one liter each) ethyl acetate and ice and, after shaking in a separatory funnel,
the layers were separated. The aqueous phase was extracted with 5 x 1000 ml. ethyl
acetate. The combined organic layers were washed with 3 x 4 liters water, 3 x 2 liters
of 0.5N hydrochloric acid, dried (MgS0
4) and concentrated to a volume of about 2.5 liters. Upon cooling, the precipitated
product which formed was collected: 9.0 g., M.P. 151-153°C. The mother liquor was
concentrated to half volume, cooled, and a second crop, 34.2 g.,M.P. 148―151°C., was
collected. Total yield by crystallization: 52.2 g. This material was shown to be primarily
a single diastereomer, designated as "Diastereomer B." Upon recrystallization from
ethyl acetate, colorless crystals were obtained, M.P. 159-161°C. This was found to
be about 90% diastereomer B.
1H―NMR (CDCI
3) ppm (delta): 1.33 (d, 3H, J=6Hz).
[0067] The mother liquor was then evaporated to dryness in vacuo to afford 68 g. of residual
oil. The oil was chromatographed on a column of silica gel (1 kg., 48―63 microns)
eluting first with eight liters of 9:1 toluene/ethyl ether then with four liters of
85:15 toluene/ethyl ether. Fractions were monitored by TLC using a 1:1 toluene/ethyl
ether solvent and developing with phosphomolybdic acid. Like fractions were combined
and evaporated in vacuo to afford 48.6 g. of oil which was predominantly "Diastereomer
A." The total yield was 52.2 g. (B) plus 48.6 g. (A) = 88.6%.
[0068] The Diastereomer A obtained above, 18 g., was triturated with ethyl acetate leaving
6.8 g. of solid material, M.P. 116-132°C. which was found to be 3:2. Diastereomer
A/Diastereomer B by NMR assay. The mother liquor from the trituration was evaporated
to dryness in vacuo to obtain 11 g. of purified Diastereomer A.
Example 6
Mixture of Diastereomers of 4a,5-Dihydro-7-hydroxy-9-(5-phenyl-2-pentyloxy)-(2H,3H,4H)-pyrido[1,2-a]-quinoline-1,6-dione
[0069] Under a nitrogen atmosphere and employing anhydrous conditions and reagents, a mixture
of 19.5 g. (0.079 mole) d/-4a,5-dihydro-7,9-dihydroxy-(2H,3H,4H)-pyrido[1,2-a]quinoline-1,6-dione,
24.0 g. (0.174 mole) potassium carbonate and 110 ml. dimethylformamide (DMF) is heated
at 90°C. for 10 minutes, then cooled to room temperature. To this mixture was added
over 5 minutes 21.0 g. (0.087 mole) 2-methylsulfonyloxy-5-phenylpentane dissolved
in 20 ml. DMF. The reaction mixture was heated at 90°C. for one hour, poured into
water (800 ml.) and extracted with ethyl acetate (4 x 500 ml.). The organic layers
were combined with sodium bicarbonate solution (3 x 300 ml.), water (300 ml.), brine
(300 ml.) and dried (MgS0
4). Evaporation of solvent in vacuo gave a residual yellow oil which was separated
by chromatography on 1.5 kg. silica gel (0.063-0.20 mm.), eluting with 2:1 by volume
toluene/ethyl ether. Fractions were monitored by TLC employing 98% ethyl ether/2%
methanol: the- starting material (dihydroxydione) R
f 0.25; product, R
f 0.40.
[0070] Similar fractions were combined and solvent evaporated in vacuo to afford 13.6 g.
(43.7%) of the title compound as a viscous yellow-orange oil.
1H―NMR (CDCl
3) ppm (delta): 1.05―4.25 (m, 19H), 6.05 and 6.9 (split doublets, meta aryl), 7.02
(s, 5H), 10.9 (s, 1H). Mass spectrum (m/e): 393 M
+.
Example 7
d/-6-Benzyloxy-8-(5-phenyl-2-pentyloxy)-3aS*,4-dihydro-(2H,3H)-pyrrolo[1,2-a]quinolin-1,5-dione
(Diastereomer A)
[0071] To a flask under a nitrogen atmosphere, is added 1.27 g. (26.54 mmole) sodium hydride
(50% suspension in oil). The oil was removed by washing with hexane (4 x 250 ml.),
then 125 ml. dimethylformamide (DMF) was added and the slurry cooled to 5°C. A solution
of 8.76 g. (23.08 mmole) of 'Diastereomer A, obtained in Example 5, in 125 ml. DMF
was added dropwise over 3-5 minutes while maintaining the reaction temperature at
or below 8°C. The mixture was then allowed to warm to room temperature and stirred
for 4 hours. The mixture was then cooled to 10°C., a solution of 4.54 g. (3.16 ml.,
26.54 mmole) benzyl bromide in 30 ml. DMF added over one minute and stirred at room
temperature for 17 hours. It was then poured into a mixture of 500 ml. each of water
and ethyl acetate, stirred and the layers separated. The aqueous phase was extracted
three times with 500 ml. portions of ethyl acetate, the combined extracts washed in
turn with 500 ml. portions each of water, 0.5N hydrochloric acid, 5% aqueous sodium
bicarbonate, brine, then dried (MgS0
4). Evaporation in vacuo gave a residual oil which was taken up in boiling ethyl ether
and hot hexane carefully added (~50 ml.) to the cloud point. The mixture was cooled
in ice and filtered to obtain 3.99 g. light yellow solid, collected in two crops.
[0072] The mother liquor was concentrated to dryness in vacuo and the residue, 6.5 g. separated
by chromatography on a column containing 420 g. silica gel, eluting with toluene/ethyl
ether. Evaporation of the product-containing fractions gave 1.2 g. of the title compound.
Total yield: 5.19 g. (48%). Several crystallizations from methanol afforded pure Diastereomer
A benzyl ether, M.P. 123-124°C.
[0073] 'H-NMR (CDCI
3) ppm (delta): 1.32 (d, 3H, J=6Hz, 8-OCHCH
3), 1.45-1.93 (m, 5H), 2.02-2.93 (m, 7H), 3.90-4.73 (m, 2H, 8-OCHCH
3 and 3a-H), 5.10 (s, broad, 2H, OCHC6
H5
), 6.23 (d, 1 H, J=2Hz, 7-H), 6.88-7.77 (m, 10H, phenyls), 7.97 (d, 1H, J=
2Hz, 9-H). Infrared (KBr) cm-': 2900 (CH), 1709, 1680 (C=0).

Example 8
d/-6-Benzyloxy-8-(5-phenyl-2-pentyloxy)-3aR*,4-dihydro-(2H,3H)-pyrrolo[1,2-a]quinoline-1,5-dione
(Diastereomer B)
[0074] Employing 17.0 g. (44.81 mmole) of Diastereomer B of 6-hydroxy-8-(5-phenyl-2-pentyloxy)-3a,4-dihydro-(2H,3H)-pyrrolo[1,2-a]quinolin-1,5-dione
obtained in Example 5 (recrystallized solids, M.P. 158-161°C.) in place of Diastereomer
A in the procedure of the previous Example, and 2.47 g. (51.53 mmole) sodium hydride,
6.13 ml. (51.53 mmole) benzyl bromide and 1000 ml. DMF, provided 15.43 g. (73.4%)
of the title compound. A purified product, M.P. 103.5-105°C. was obtained after several
recrystallizations from ethyl ether. 'H-NMR (CDCI
3) ppm (delta): 1.31 (d, 3H, J=6Hz, 8-OCHCH
3), 1.53-2.02 (m, 5H), 2.09-2.92 (m, 7H), 4.03-4.80 (m, 2H, 8-OCHCH
3 and 3a-H), 5.11 (s, broad, 2H, OCH
2C
6H
5), 6.24 (d, 1H, J=2Hz, 7-H), 6.72-7.68 (m, 10H, phenyls), 7.98 (d, 1H, J=2Hz, 9-H).
Infrared (KBr) cm-': 2900 (CH), 1690, 1650 (C=O). High resonance mass spectrum molecular
ion:

[0075] Base peak (m/e) 91.

Example 9
d/-6-Benzy[oxy-5-hydroxy-5-ethoxycarbonylmethyl-8-(5-phenyl-2-pentyloxy)-3aS*,4-dihydro-(2H,3H)-pyrrolo[1,2-a]quinolin-1-one
(Diastereomer A)
[0076] Under a nitrogen atmosphere employing anhydrous reagents and conditions, to a round
bottomed flask was charged 8.24 mi. n
-butyllithium (2.4M in hexane, 19.8 mmole) and tetrahydrofuran (THF), 10 ml. The mixture
was cooled to -78°C., a solution of 2.78 ml. (19.8 mmole) diisopropylamine in 10 ml.
THF was added dropwise over two minutes while maintaining the internal temperature
below -65°C. Then a solution of 1.93 ml. (19.8 mmole) ethyl acetate in 5 mi. THF was
added dropwise over 2 minutes at the same temperature (<-65°C.). When the addition
was complete, the reaction mixture was stirred at -78°C. for 0.25 hour. To this was
added 7.14 g. (15.2 mmole) d/-6-benzyloxy-8-(5-phenyl-2-pentyloxy)-3aS*,4-dihydro(2H,3H)-pyrrolo[1,2-a]quinoline-1,5-dione,
Diastereomer A, M.P. 122-125°C. provided in Example 7, dissolved in 80 ml. THF. This
addition was also carried out below -65°C. The reaction mixture was stirred for 0.3
hour, then 1.13 ml. (19.8 mmole) acetic acid was added, followed by 75 ml. water.
The organic solvents were evaporated in vacuo at room temperature, the aqueous residue
diluted with 500 ml. ethyl ether and 100 ml. water, the mixture shaker and the layers
separated. The ether layer was washed (150 ml. each) with 0.5N hydrochloric acid,
sodium bicarbonate solution, brine, dried (MgS04) and the ether evaporated in vacuo
to afford 8.37 g. of product as a colorless solid. 'H-NMR (CDCl
3) ppm (delta): 0.79-1.43 (m, 6H, methyls), 1.47-2.33 (m, 7H), 2.37-2.97 (m 6H), 6.5
(d, 1 H, J=14Hz), 3.77-4.63 (m, 4H), 4.70 (s, broad, OH), 5.13 (s, broad, 2H), 6.4
(d, 1H, J=2Hz), 7.00-7.67 (m, 10H, phenyls), 8.27 (d, 1H, J=2Hz).
Example 10
d/-5,6-Dihydroxy-5-Ethoxycarbonylmethyl-8-(5-phenyl-2-pentyloxy)-3aS*,4-dihydro(2H,3H)pyrrolo[1,2-a]quinolin-1-one
(Diastereomer A)
[0077] The benzyl ether obtained in the previous Example, (8.27 g., 14.85 mmole) was dissolved
in 500 ml. ethanol, 6 g. palladium/carbon (5%) was added and the mixture was hydrogenated
at 40-50 psi (2.8-3.5 kg./cm.
2) for 0.66 hour. The catalyst was removed by filtration, and the filtrate was evaporated
in vacuo. The residue was taken up in methylene chloride, filtered, and evaporated
in vacuo to afford 6.59 g. colorless foam (95%).
[0078] 'H-NMR (CDCI
3) ppm (delta): 1.10―1.45 (m, 6H, methyls), 1.48-2.25 (m, 7H), 2.26-2.97 (m, 6H), 3.22
(d, 1 H, J=14Hz), 3.75-4.63 (m, 4H), 5.4 (s, broad, OH), 6.25 (d, 1 H, J=2Hz), 7.0-7.42
(m, 5H), 7.93 (d, 1 H, J=2Hz), 8.83 (s, broad, OH).
Example 11
d/-6-Acetoxy-5-Ethoxycarbonylmethylene-8-(5-phenyl-2-pentyloxy)-3aS*,4-dihydro-(2H,3H)-pyrrolo[1,2-a]quinolin-1-one
(Diastereomer A)
[0079] The product obtained in the previous Example, 6.49 g. (13.90 mmole) was dissolved
in 350 ml. methylene chloride, 30 ml. (21.5 mmole) triethylamine and 4.3 ml. (45 mmole)
acetic anhydride were added and the mixture stirred at room temperature for 0.75 hours.
Aqueous sodium bicarbonate solution, 50 mi., was added and the organic solvent was
evaporated in vacuo. The aqueous residue was shaken with 700 mi. ethyl ether, the
extract washed with 400 ml. water, 200 mi. 0.5N hydrochloric acid, 400 ml. brine and
dried over anhydrous magnesium sulfate. Evaporation of the ether, in vacuo at room
temperature, gave an opaque oil. This was taken up in hot methanol (~65 ml.), upon
cooling a colorless solid precipitated, 5.59 g., M.P. 98-102°C.
[0080] 'H-NMR (CDCI
3) ppm (delta): 1.03-1.47 (m, 6H), 1.49―2.12 (m, 6H), 2.17―2.32 (m, 4H), 2.33―2.87
(m, 6H), 3.63-4.70 (m, 4H), 6.27-6.50 (m, 2H), 6.97-7.53 (m, 5H), 8.40 (d, 1 H, J=2Hz).
Example 12
d/-6-Acetoxy-5-Ethoxycarbonylmethyl-8-(5-phenyl-2-pentyloxy)-3,3aS*,4,5-tetrahydro-(2H)pyrrolo[1,2-a]quinolin-1-one
(Diastereomer A)
[0081] The olefin obtained in the previous Example, 3.50 g. (7.13 mmole), was dissolved
in 250 ml. ethyl acetate, 3.50 g. 5% Pd/C catalyst was added and the mixture was hydrogenated
at 40-50 psi (2.8-3.5 bar) for four hours. The catalyst was removed by filtration,
washing with 3 x 80 ml. ethyl acetate. The combined filtrate and washings were evaporated
in vacuo, the residual oil dissolved in 135 ml. boiling methanol and the resulting
solution allowed to cool. Upon filtration, 2.32 g. of product, M.P. 94-96°C. was obtained.
The mother liquor was concentrated in vacuo to an oil, and the oil triturated with
ethyl ether to provide a second crop, 0.28 g., M.P. 94-96°C.
[0082] 'H-NMR (CDCI
3) ppm (delta): 1.025-1.308 (m, 6H), 1.325-1.858 (m, 6H), 2.075-2.342 (m, 4H), 2.350-2.733
(m, 5H), 3.062 (q, 2H, J=
3, 14
Hz), 3.250-3.375 (m, 1 H), 3.533-3.850 (m, 1 H), 4.235 (q, 2H, J=
6, 6Hz), 4.267―4.442 (m, 1H), 6.39 (d, 1H, J=2Hz), 7.067-7.500 (m, 5H), 8.008 (d, 1H,
J=
2Hz). Infrared (KBr) cm-': 2900, 1830, 1760, 1690. High resonance mass spectrum:

Example 13
d/-6-Acetoxy-5-Ethoxycarbonylmethyl-8-(5-phenyl-2-pentyloxy)-3,3aR*,4,5-tetrahydro-(2H)-pyrrolo[1,2-a]quinolin-1-one
(Diastereomer B)
[0083] When the procedure of Example 9 is carried out, but starting with Diastereomer B
of d/-6-benzyloxy-8-(5-phenyl-2-pentyloxy)-3a,4-dihydro-(2H,3H)-pyrrolo[1,2-a]quinolin-1,5-dione,
provided in Example 8, in place of the Diastereomer A, the corresponding product is
obtained in like manner. This product is carried, in turn, through the procedures
of Example 10, 11 and 12, but with the following modifications, to provide the title
compound:
[0084] In the procedure of Example 10, the debenzylation was carried out with 250 ml. ethyl
acetate instead of 500 ml. ethanol. The product obtained was a solid, M.P. 123-125°C.
[0085] In the procedure of Example 11, the product obtained was a solid, M.P. 80.5―83.5°C.
[0086] In the procedure of Example 12, the product obtained was a milky oil.
[0087] The overall yield was 78%.
Example 14
d/-6-Acetoxy-5-(2-Acetoxyethyl)-8-(5-phenyl-2-pentyloxy)-1,2,3,3aS*,4,5-hexahydropyrrolo[1,2-a]quinoline
Hydrochloride (Diastereomer A)
[0088] Under anhydrous conditions and a nitrogen atmosphere, 2.235 g. (4.53 mmole) d/-6-acetoxy-5-ethoxycarbony[methyl-8-(5-phenyl-2-pentyloxy)-3,3aS*,4,5-tetrahydro-(2H)-pyrrolo[1,2-a]quinolin-1-one
(Diastereomer A), provided in Example 12, was dissolved in 100 ml. anhydrous tetrahydrofuran,
0.688 g. (18.13 mmole) lithium aluminum hydride was added and the mixture refluxed
for two hours. The mixture was cooled to -6°C. and 20 ml. 10% by weight aqueous sodium
hydroxide was added dropwise over 10 minutes at such a rate that the temperature did
not exceed 0°C. The resulting mixture was filtered, washing with 5 x 200 ml. ethyl
acetate. The filtrate and washings were combined and washed with 500 ml. brine, dried
(MgS0
4) and the solvent evaporated in vacuo to afford 1.87 g. of off-white foam. The foam
was dissolved in 20 ml. methylene chloride, 2 ml. (21.1 mmole) acetic anhydride and
4 ml. (28.6 mmole) triethylamine were added and the mixture stirred overnight at ambient
temperature. After addition of 600 ml. ethyl ether, the layers were separated, the
ether phase was washed with 250 ml. brine, dried (MgS0
4) and the ether evaporated in vacuo to yield 2 g. of light green oil. Column chromatography
on 110 g. silica gel (48-63 microns), eluting with two liters of 95:5 toluene/ethyl
ether afforded 1.65 g. of product as the free base (oil). The free base was dissolved
in 250 ml. ethyl ether and 20 ml. of hydrogen chloride saturated ethyl ether was added.
The precipitated solid was collected by decantation of ether, washing with 2 x 25
ml. of the same solvent. Residual solvent was removed in vacuo to afford a clear glassy
solid.
[0089] 'H-NMR (free base) (CDCI
3) ppm (delta): 1.27 (d, 3H), 1.38-3.54 (m, 18H), 2.03 (s, 3H), 2.29 (s, 3H), 3.88-4.40
(m, 3H), 5.92 (s, 2H), 6.92-7.64 (m, 5H). Infrared (CHCI
3) microns: 3.45, 5.65, 5.75. High resonance mass spectrum (M
+):

[0090] Diastereomer B of the title compound was obtained by the same procedure and in the
same yield as above, but employing as starting material the product obtained in Example
13.
Example 15
Mixed Diastereomers of d/-7-Acetoxy-(2-Acetoxyethyl)-9-(5-phenyl-2-pentyloxy)-2,3,4,4a,5,6-hexahydro-(1H)-pyrido[1,2-a]quinoline
Hydrochloride
[0091] When the procedures of Examples 8 through 12 are repeated in turn, but starting with
the mixture of diastereomers of 4a,5-dihydro-7-hydroxy-9-(5-phenyl-2-pentyloxy)-(2H,3H,4H)-pyrido[1,2-a]quinoline-1,6-dione
in the procedure of Example 8, the title compound is obtained in like manner as a
mixture of diastereomers.
Example 16
Methyl d/2-[1-(3,5-Dimethoxyphenyl)pyrrolidin-2-yl]Acetate
A. 2-Tetrahydrofurfuryl bromide
[0092] To 2-tetrahydrofurfuryl alcohol (20.4 g.) and triphenylphosphine (58 g.) was added
over 1.5 hours 32.5 g. N-bromosuccinimide. The reaction mixture was distilled at reduced
pressure to afford 20 g. of product. Redistillation gave 15 g. pure bromide, B.P.
38―40°C. (2 mm.).
B. 2-Cyanomethylltetrahydrofuran
[0093] To a solution of 1.3 g. (5 mmole) 18-crown-6 and 9.05 g. (0.05 mole) 2-tetrahydrofurfuryl
bromide in 80 ml. acetonitrile was added 16.25 g. (0.25 mole) potassium cyanide. The
mixture was heated at 90°C. for 48 hours, cooled, filtered, washing with ethyl ether
and the filtrate and washings evaporated in vacuo without heating. The residue was
distilled to afford 4.25 g. (77%) of product, B.P. 50°C. (2 mm.). 'H-NMR (CDCl
3) ppm (delta): 2.60 (d, 2H, CH
2CN).
C. 2-(Tetrahydrofuran-2-yl)acetic acid
[0094] A solution of 90 g. (0.81 mole) 2-cyanomethyltetrahydrofuran, 130 g. (3.2 mole) sodium
hydroxide, 250 ml. methanol and 300 ml. water was heated at reflux for 20 hours. The
reaction mixture was evaporated in vacuo, the residue taken up in chloroform and acidified
to pH 5 with 6N hydrochloric acid. The organic layer was separated, the aqueous phase
extracted with chloroform, the combined extracts dried (MgS0
4) and the solvent evaporated to give 62 g. of crude acid. Distillation afforded 52.6
g. of product, B.P. 110°C. (2 mm.).
1H―NMR (CDCl
3) ppm (delta): 2.50 (d, 2H, CH
2COOH), 11.10 (s, 1H, COOH).
D. Methyl 3,6-dibromocaproate
[0095] To 800 mi. glacial acetic acid saturated with anhydrous hydrogen bromide was added
56 g. 2-(tetrahydrofuran-2-yl)acetic acid in one portion and the mixture heated at
100°C. for 60 hours. The volatiles were evaporated, the residue taken up in ethyl
ether and washed.with water. The ether layer was dried (MgS0
4) and solvent evaporated to afford 120 g. of crude 3,6-dibromocaproic acid. Distillation
gave 115 g. of product, B.P. 116-124°C. (2 mm.).
1H―NMR (CDCl
3) ppm (delta): 3.00 (d, 2H, CH
2COOH), 3.40 (m, 2H), 4.30 (m, 1H).
[0096] Esterification in refluxing methanolic hydrogen chloride gave 118 g. of methyl ester.
1H―NMR (CDCl
3) ppm (delta): 2.90 (d, 2H), 3.45 (m, 2H), 3.70 (s, 3H), 4.30 (m, 1H).
[0097] E. Under a nitrogen atmosphere, a mixture of 52 g. (0.340 mole) 3,5-dimethoxyaniline,
108.8 g. (0.378 mole) methyl d/-3,6-dibromocaproate, 60 ml. pyridine and 160 mi. tetrahydrofuran
were stirred at room temperature overnight. The tetrahydrofuran was distilled off
at atmospheric pressure and the remaining mixture heated at 100°C. for 2.5 hours.
Additional methyl d/-3,6-dibromocaproate (5.7 g.) and pyridine (3.16 ml.) was added
and heating at 100°C. resumed for an additional 2.5 hours. The pyridine was evaporated
in vacuo, the residue partitioned between water and methylene chloride, the aqueous
phase extracted with 4 x 150 ml. methylene chloride and the combined organic layers
washed with 75 mi. 1 N hydrochloric acid, 75 ml. water and 75 ml. brine. The washed
extracts were dried (MgS0
4) and solvent evaporated to afford 57.5 g. of orange solid.
[0098] The aqueous phase was adjusted to pH 9 with 6N sodium hydroxide, extracted with 4
x 100 ml. methylene chloride, the extracts washed with water, brine, dried (MgS0
4) and evaporated in vacuo to afford 16.7 g. of residual oil. The orange solid was
placed on a silica gel column and eluted with methylene chloride/ethyl acetate.
[0099] The product fractions were combined and evaporated in vacuo to afford 53.6 g. (56%)
of product. 'H-NMR (CDCI
3) ppm (delta): 3.70 (s, 3H,―COOCH
3), 3.78 (s, 6H, OCH
3), 5.80 (s, 3H, aromatic).
Example 17
d/-2-[1-(3,5-Dimethoxyphenyl)pyrrolidin-2-yl]acetic Acid
[0100] A mixture of 53.6 g. (0.192 mole) methyl d/-2-[1-(3,5-dimethoxyphenyl)pyrrolidin-2-yl]acetate,
250 ml. methanol and 22.8 g. (0.57 mole) sodium hydroxide in 200 ml. water was stirred
at room temperature for 2.5 hours. The methanol was evaporated and the aqueous residue
cooled in ice. To this was added dropwise 48 mi. concentrated hydrochloric acid, the
mixture extracted with 4 x 150 ml. methylene chloride, the extract washed with water,
dried (MgS0
4) and the solvent evaporated to afford 48.9 g. (96%) of product. 'H-NMR (CDCI
3) ppm (delta): 3.80 (s, 6H, OCH
3), 4.10 (m, 1H, N-CH), 5.82 (s, 3H, aromatic), 11.0 (s, 1H, COOH). Mass spectrum (m/e):
206 (base peak), 265 (M
+).
Resolution via alpha-Methylbenzylamine Example 18
Resolution via alpha-Methylbenzylamine Salt
A. Dextrorotatory salt
[0101] A mixture of 52.3 g. (0.197 mole) d/-2-[1-(3,5-dimethoxyphenyl)pyrrolidin-2-yl)acetic
acid and 370 ml. ethyl acetate was heated to affect solution, 24.4 g. (0.201 moles)
d-(+)-alpha-methylbenzylamine was added. The mixture was stirred for 10 minutes, then
allowed to stand at room temperature for three hours to initiate crystallization.
Then 370 ml. ethyl ether was added and the resulting mixture refrigerated overnight.
Filtration and washing with cold ether gave 72.2 g. of solids. Evaporation of the
mother liquors afforded an additional 4.7 g. of brown solid.
[0102] To the first crop (72.2 g.) was added 1440 ml. ethyl acetate and the mixture heated
until a solution was obtained. The solution was allowed to stand overnight at room
temperature, filtered, the crystals washed with cold ether and dried in vacuo to afford
40.9 g., M.P. 129-130°C., [alpha]
D +13.5°. After two recrystallizations from ethyl acetate, 9.7 g. of pure salt was
obtained,.M.P. 141-142°C., [alpha]
D +32°.
B. Levorotatory salt .
[0103] The mother liquors from above were acidified with 167 ml. 1 N hydrochloric acid,
extracted with 5 x 125 ml. ethyl acetate, the extracts combined, washed with brine,
dried (MgS0
4) and the solvent evaporated to obtain 49 g. of residue. This was dissolved in 350
ml. warm ethyl acetate, 22.4 g. 1-(-)-alpha-methylbenzylamine added and the solution
cooled to room temperature. Ethyl ether, 350 ml. was added and the mixture refrigerated
overnight. The precipitated solid was collected by filtration, washed with cold ether
and dried in vacuo to obtain 44.0 g. of salt. This was dissolved in 880 ml. ethyl
acetate and set aside at room temperature for six hours. Filtration gave 12.4 g.,
M.P. 139-140°C. After standing overnight, the mother liquor afforded a second crop,
11.66 g., M.P. 139-140°C. The optical rotation (in chloroform) for the first crop
was [alpha]
D -30.9°, and [alpha]
D -26.6° for the second crop.
[0104] The two crops were combined and recrystallized from 480 ml. ethyl acetate to afford
18.0 g. of salt, M.P. 141-142°C., [alpha]
D -34.4°.
Example 19
A. d-(+)-2-[1-(3,5-dimethoxyphenyl)pyrrolidin-2-yl]-acetic acid
[0105] The dextrorotatory salt, obtained in the previous Example, 22.0 g., was recrystallized
from ethyl acetate (440 ml.) to obtain 17.5 g. of salt, M.P. 142-143°C., [alpha]
D +33.8°. This was treated with 47 ml. 1N hydrochloric acid, extracted with 4 x 100
ml. ethyl acetate, and the extracts washed with brine and dried over magnesium sulfate.
Evaporation of solvent in vacuo gave 12.9 g. of d-(+)-acid as a green oil. A portion
was decolorized by passing it through a short column of silica gel, [alpha]
D +31.4°.
B. 1-(-)-2-[1-(3,5-dimethoxyphenyl)pyrrolidin-2-yl]-acetic acid
[0106] To 18.0 g. of the levorotatory salt obtained in the previous Example, was added 46.5
ml. 1N hydrochloric acid and the resulting mixture worked up as in Part A, above,
to obtain 13.2 g. of product [alpha]
D -36.4°.
Example 20
dl-, d-(+)- and l-(-)-6,8-Dimethoxy-2,3,3a,4-tetrahydro-1H-pyrrolo[1,2-a]quinolin-5-one
A. Dextrorotatory isomers
[0107] A mixture of 13.2 g. (46.5 mmole) l-(-)-2-[1-(3,5-dimethoxyphenyl)pyrrolidin-2-yl]acetic
acid, 6.5 g. sodium acetate, 100 ml. acetic acid and 100 ml. acetic anhydride was
heated on the steam bath for 35 minutes. The volatiles were evaporated in vacuo, the
residue mixed with methylene chloride, and the organic layer separated. After washing
the organic phase with sodium bicarbonate solution (3 x 50 ml.), drying (MgS0
4) and evaporation of solvent, 11.2 g. (91%) of crude product was obtained. A 300 mg.
portion was crystallized from methylene chloride/hexane, m.p. 126-127°C., [alpha]
D +141° (c = 1, CHCI
3). Mass spectrum (m/e): 247 M
+.
B. Levorotatory isomers
[0108] A mixture of 12.9 g. (48.6 mole) d-(+)-2-[1-(3,5-dimethoxyphenyl)pyrrolidin-2-yl]acetic
acid, 6.4 g. sodium acetate and 50 ml. each of acetic acid and acetic anhydride gave
11.2 g. of crude product by the above procedure. Recrystallization of a portion from
methylene chloride gave purified isomer, m.p. 129―130°C., [alpha]
D -146.2° (c = 1, CHCI
3).
Racemate
[0109] By the same procedure, d/-2-[1-(3,5-dimethoxyphenyl)pyrrolidin-2-yl]acetic acid is
converted to dl-6,8-dimethoxy-2,3,3a,4-tetrahydro-1H-pyrrolo[1,2-a]quinolin-5-one.
Example 21
d/-, d-(+)- and l-(-)-6,8-Dihydroxy-2,3,3a,4-tetrahydro-1H-pyrrolo[1,2-a]quinolin-5-one
A. Dextrorotatory isomer
[0110] A mixture of 11.2 g. (45.3 mmole) d-(+)-6,8-dimethoxy-2,3,3a,4-tetrahydro-1 H-pyrrolo[1,2-a]quinolin-5-one
and 100 mi. each of acetic acid and 48% hydrobromic acid was heated under a nitrogen
atmosphere at 67°C. for 2.5 hours. The reaction mixture was concentrated in vacuo,
the residue mixed with water and adjusted to pH 7.0 with sodium bicarbonate solution.
The neutral mixture was extracted with 6 x 100 ml. ethyl acetate, the combined extracts
washed with brine, dried (MgS04) and the solvent evaporated in vacuo to afford 9.0
g. (91 %) of product as a yellow solid. A 100 mg. sample was crystallized from chloroform,
m.p. 202-203°C., [alpha]
D +108° (c = 1, CHCI
3). Mass spectrum (m/e): 218 (base peak), 219 (M
+).
B. Levorotatory isomer
[0111] By the same procedure 10.2 g. l-(-)-6,8-dimethoxy-2,3,3a,4-tetrahydro-1 H-pyrrolo[1,2-a]quinolin-5-one
and 50 mi. each of acetic acid and 48% hydrobromic acid afforded 9.2 g. of product,
m.p. 190-192°C., [alpha]
D -91.4° (c = 1, CHCI
3).
Racemate
[0112] By the same procedure d/-6,8-dimethoxy-2,3,3a,4-tetrahydro-1H-pyrrolo[1,2-a]quinolin-5-one
is converted to d/-6,8-dihydroxy-2,3,3a,4-tetrahydro-1H-pyrrolo[1,2-a]quinolin-5-one.
Example 21C
6-Hydroxy-8-(5-phenyl-2R-pentyloxy)-2,3,3aS,4-tetrahydro-1H-pyrrolo[1,2-a]quinolin-5-one
[0113] A mixture of 7.4 g. (33.8 mmole) d-(+)-6,8-dihydroxy-2,3,3a,4-tetrahydro-1H-pyrrolo[1,2-a]quinolin-5-one,
9.55 g. (69.2 mmole) powdered potassium carbonate and 37 ml. dimethylformamide was
heated to 80°C. under a nitrogen atmosphere, 8.391 g. (34.6 mmole) 5-phenyl-2S-pentyl
mesylate is added and heating at 80°C. continued for 90 minutes. The dimethylformamide
was evaporated in vacuo, the residue extracted with 5 x 50 mi. methylene chloride
and the combined extracts washed with water, brine, and dried (MgS0
4). Evaporation of solvent in vacuo afforded 13.7 g. of crude product which was purified
on a column of silica gel, eluting with a mixture of equal volumes of methylene chloride
and hexane and methylene chloride/ethyl acetate. The product fractions were combined
and evaporated to provide 8.52 g. of the desired product.
1H―NMR (CDCI
3) ppm (delta): 1.30 (d, 3H), 5.35 (m, 1H), 5.65 (m, 1H), 7.1 (s, 5H), 12.7 (s, 1H,
OH).
Example 21 D
6-Acetoxy-8-(5-phenyl-2R-pentyloxy)-2,3,3aS,4-tetrahydro-1H-pyrrolo[1,2,-a]quinolin-5-one
[0114] A mixture of 3.138 g. (8.6 mmole) of the 6-hydroxy compound obtained in the preceding
Example, 30 mi. pyridine and 9 ml. acetic anhydride was-heated, under nitrogen, at
80°C. overnight. The pyridine was removed by evaporation in vacuo, the residue taken
up in methylene chloride, washed with water and dried (MgS0
4). Evaporation of solvent afforded a residual oil which was purified by chromatography
on a silica gel column, eluting with methylene chloride. The product-containing fractions
were combined and the solvent evaporated in vacuo to provide 2.193 g. of the desired
product. Reaction of the combined less polar fractions (1.11 g.) with fresh acetic
anhydride by the above procedure and work-up as above gave an additional 1.105 g.
of product.
1H―NMR (CDCl
3) ppm (delta): 1.30 (d, 3H), 2.30 (s, 3H), 5.80 (s, 2H, aromatic), 7.20 (s, 5H, phenyl).
Example 21E
6-Hydroxy-5-Carboxymethylene-8-(5-phenyl-2R-pentyloxy)-2,3,3aS,4-tetrahydro-1 H-pyrrolo[1,2-a]quinoline
Lactone
[0115] Under a nitrogen atmosphere and anhydrous conditions 70 ml. dry tetrahydrofuran was
cooled to -5°C. and 1.490 g. (14.76 mmole) diisopropylamine was added followed by
dropwise addition of 9.22 mi. (14.76 mmole) n-butyllithium in hexane while keeping
the mixture below 0°C. After the addition was completed, the mixture was stirred at
-5°C. for 30 minutes and cooled to -67°C. Ethyl acetate (648 mg., 7.36 mmole) was
added dropwise while keeping the reaction mixture below -67°C. After the addition,
the resulting mixture was stirred at -67°C. for one hour. To this was added 1.989
g. (4.9 mmole) of the 6-acetoxy compound, obtained in the preceding Example, dissolved
in 10 mi. tetrahydrofuran and the resulting mixture stirred at -74°C. for 3.5 hours.
Acetic acid was added to adjust the mixture to pH 5.5. After allowing to warm to room
temperature, the mixture was extracted with methylene chloride, the combined extracts
washed with water, dried (MgS0
4) and the solvent evaporated at reduced pressure. The residual oil was chromatographed
on silica gel, eluting with methylene chloride/hexane and finally with ethyl acetate.
Product fractions were combined and evaporated to dryness to yield 1.13 g. of the
title lactone. 'H-NMR (CDCI
3) ppm (delta): 1.30 (d, 3H), 5.70 (m, 2H, aromatic), 6.05 (m, 1 H, olefin), 7.10 (s,
5H, phenyl).
Examples 21 F
2-[6-Hydroxy-8-(5-phenyl-2R-pentyloxy)-1,2,3,3aS,4,5R-hexahydropyrrolo[1,2-a]quinolin-5-yl]acetic
Acid Lactone
[0116] A solution of 1.157 g. (2.98 mmole) of the unsaturated lactone obtained in the previous
Example in 100 ml. methanol was heated to 50°C., and 15 ml. 5N sodium hydroxide and
1.41 g. of Raney alloy was added, the latter being added in portions over about five
minutes. The mixture was then stirred at 55°C. for 3.5 hours, filtered to remove the
Raney alloy, the cake washed with methanol and the solvent evaporated in vacuo. To
the residue, 75 ml. 1N hydrochloric acid was added, the precipitated solid was extracted
with ethyl acetate, the extracts dried (MgS0
4) and evaporated to obtain 622 mg. of crude product as an oil. The oil was purified
by chromatography on silica gel, eluting with methylene chloride (15 fractions), ethyl
acetate (3 fractions) and stripping the column with methanol, the product containing
fraction combined (fractions 2-10) and evaporated in vacuo to provide 322 mg. of the
desired lactone.
1H―NMR (CDCl
3) ppm (delta): 1.30 (d, 3H), 4.15 (m, 1H), 5.57-5.93 (m, 2H), 7.08 (s, 5H).
Example 21G
6-Hydroxy-5-(2-Hydroxyethyl)-8-(5-phenyl-2R-pentyloxy)-1,2,3,3aS*,4,5R*-hexahydropyrrolo[1,2-a]quinoline
[0117] A mixture of 10 ml. dry tetrahydrofuran and 340 mg. (0.87 mmole) of the saturated
lactone obtained in the preceding Example was stirred to affect solution, 33 mg. (0.87
mmole) lithium aluminum hydride added and the mixture stirred at room temperature
for two hours. The reaction was quenched by addition of a few drops of water, the
pH adjusted to 6.0 with 1N hydrochloric acid and the mixture extracted with ethyl
acetate. The combined extracts were washed with brine, dried (MgS0
4) and the solvent evaporated in vacuo to afford 344 mg. residual oil. The oil was
placed on a silica gel column and eluted with methylene chloride/ethyl acetate and
stripped with methanol. Product fractions were combined and evaporated to dryness
in vacuo to yield 323 mg. of an oil, [alpha]
D +46.5 (c = 1, CHCI
3).
1H―NMR (CDCl
3) ppm (delta): 1.20 (d, 3H), 3.60 (t, 2H, CH
2OH), 4.10 (m, 1H), 5.65 (m, 2H), 7.10 (s, 5H).
Example 22
Methyl d/-2-[1-(3,5-dimethoxyphenyl)-piperidin-2-yl]acetate
A. 2-Cyanomethyltetrahydropyran
[0118] Repeating the procedure of Example 16, Part B, but employing 2-chloromethyltetrahydropyran
in place of 2-tetrahydrofurfuryl bromide and heating for 6 days gave a 52% yield of
product, B.P. 65-74°C. (3 mm.). 'H-NMR (CDCI
3) ppm (delta): 2.50 (d, 2H, CH
2CN).
B. 2-(Tetrahydropyran-2-yl)acetic acid
[0119] Alkaline hydrolysis of the above nitrile by the procedure of Example 16, Part C,
gave the desired product, M.P. 46-50°C. in 77% yield.
C. Methyl 3,5-dibromoheptanoate
[0120] Treatment of the above acid with HBr/acetic acid by the procedure of Example 16,
Part D gave a 94% yield of 3,7-dibromoheptanoic acid.'H-NMR (CDCI
3) ppm (delta): 2.90 (d, 2H), 4.30 (m, 1 H), 11.30 (s, 1 H)..
[0121] The dibromo acid was esterified in methanol saturated with dry hydrogen chloride
to give the desired methyl ester in 95% yield.'H-NMR (CDCI
3) ppm (delta): 3.95 (d, 2H, CH
2COOCH
3), 4.35 (m, 1 H, 3-position), 4.75 (s, 3H, COOCH
3).
[0122] D. By the procedure of Example 16, 23.7 g. (0.155 mole) 3,5-dimethoxyaniline and
52.3 g. (0.173 mole) of methyl 3,7-dibromoheptanoate, 26.9 g. pyridine and 80 ml.
tetrahydrofuran (THF) were combined and stirred overnight at room temperature. The
THF was removed by distillation at atmospheric pressure and an additional 5.8 g. 3,7-dibromoheptanoate
and 3.3 g. of pyridine were added. The mixture was heated at 100°C. for five hours,
then concentrated in vacuo. The residue was dissolved in methylene chloride and worked
up as described in Example 16 to afford 38 g. of crude product. The crude material
was taken up in toluene and placed on a column of 400 g of silica gel and eluted with
ethyl acetate/methanol. Product fractions were combined and evaporated to dryness
to give 14.6 g. of material: 'H-NMR (CDCI
3) ppm (delta): 2.58 (d, 2H, CH
2CO
2CH
3), 3.64 (s, 3H, CO
2CH
3), 3.78 (s, 6H, OCH
3), 4.30 (m, 1H,―NCH―CH
2CO
2CH
3), 6.2-5.8 (m, 3H, aromatic).
Example 23
d-, l- and d/-2-[1-(3,5-Dimethoxyphenyl)piperidin-2-yl]acetic Acid
[0123] A mixture of 14.5 g. (0.049 mole) methyl d/-2-[/-3,5-dimethoxyphenyl)piperidin-2-yl]acetate,
49 ml. 5N sodium hydroxide and 100 mi. methanol was stirred at room temperature overnight.
Water, 250 ml. was added, the mixture acidified with 1 N hydrochloric acid to pH 5
and extracted with ethyl acetate. The extracts were combined, washed with brine, dried
(MgS0
4) and evaporated in vacuo to yield 12.2 g. (90%) of d/ product as an oil.
1H―NMR (CDCl
3) ppm (delta): 2.55 (d, 2H, CH
2COOH), 3.80 (s, 6H), 6.30―5.80 (m, 3H), 11.0 (s, 1H, COOH).
Example 24
d; /- and d/-3,4,4a,5-tetrahydro-7,9-dimethoxy-1H,2H-pyrido[1,2-a]quinolin-6-one
[0124] Under a nitrogen atmosphere, a mixture of 12.1 g. (0.043 mole) d/-2-[1-(3,5-dimethoxyphenyl)piperidin-2-yl]acetic
acid, 100 mi. glacial acetic acid, 6.0 g. sodium acetate and 100 mi. acetic anhydride
was stirred at room temperature overnight. The acetic acid and acetic anhydride were
removed by evaporation in vacuo, the residue partitioned between methylene chloride
and saturated aqueous sodium bicarbonate solution, and the organic phase washed with
sodium bicarbonate, water, brine and dried (MgS0
4). The extracts were evaporated to dryness to give 13 g. of a green oil. The oil was
purified by chromatography on a column containing 300 g. of silica gel, eluting with
ethyl acetate. Product fractions were combined and evaporated to afford 5.5 g. of
the desired dl product, M.P. 91―94°C.
1H―NMR (CDCI
3) ppm (delta): 2.50 (m, 2H, CH
2CO), 3.79 (s, 3H), 3.81 (s, 3H), 5.90 (m, 2H). After recrystallization from isopropyl
ether, 2.6 g. of crystals were obtained, M.P. 92-93°C.
Example 25
d/-6-Ethoxycarbonylmethyl-6-hydroxy-7,9-dimethoxy-1,2,3,4,4a,5-hexahydropyrido(1,2-a)quinoline
[0125] To a solution of 5.05 g. (0.05 mole) diisopropylamine in 100 ml. tetrahydrofuran
(THF) under a nitrogen atmosphere and anhydrous conditions at 0°C. was added dropwise
31.25 ml. (0.05 mole) 1.6M n-butyllithium in hexane, the mixture stirred at 0°C. for
20 minutes, then cooled to -78°C. A solution of 4.4 g. (0.05 mole) ethyl acetate in
20 ml. THF was added dropwise, the resulting mixture stirred at -78°C. for one hour,
then a solution of 3.0 g. (0.0115 mole) dl-7,9-dimethoxy-6-oxo-1,2,3,4,4a,5-hexahydropyrido[1,2-a]quinoline
in 20 ml. THF was added dropwise over 30 minutes. The mixture was stirred for 15 minutes
after the addition was completed, quenched by addition of 3.6 g. acetic acid at -78°C.
and poured into water. Extraction with ethyl ether and evaporation of solvent from
the extracts gave 4.0 g. of crude product. This was purified by chromatography on
200 g. silica gel, eluting with ethyl ether afforded 3.0 g. of purified product.
1H―NMR (CDCI
3) ppm (delta): 1.35 (t, 3H), 4.20 (q, 2H), 4.70 (s, 1H, OH), 5.90 (m, 2H, aromatic).
[0126] The less polar chromatography fractions were combined and evaporated to dryness to
give 600 mg. of olefinic material.
Example 26
[0127]

[0128] To a suspension of 6 g. of florisil in 30 ml. benzene was added 3.0 g. of dl - 6
- ethoxycarbonylmethyl - 6 - hydroxy - 7,9 - dimethoxy - 1,2,3,4,4a,5 - hexahydropyrido[1,2
- a]quinoline and the mixture was heated at reflux for two hours. Thin-layer chromatography
of a sample on a silica gel plate, eluting with ethyl ether showed two spots, R
f 0.7 and 0.5, identical to the less polar fraction (600 mg.) obtained in the previous
Example.
[0129] The above reaction mixture was filtered to remove florisil and the benzene evaporated
to give 2.6 g. of crude material which was combined with the less polar mixture (600
mg.) from the previous Example. The crude mixture (3.2 g.) was placed on a silica
gel column and eluted with hexane/ethyl ether to afford 1.5 g. of LP product (R
f 0.7) with infrared carbonyl band at 1715 cm-' and 1.5 g. of MP material (R
f 0.5) with infrared carbonyl band at 1750 cm-'.
[0130] The LP product was identified by its
1H―NMR spectrum as dl - 6 - ethoxycarbonylmethylene - 7,9 - dimethoxy - 1,2,3,4,4a,5
- hexahydropyrido[1,2 - a]quinoline.
[0131] The MP product was likewise identified as d/ - 6 - ethoxycarbonylmethyl - 7,9 - dimethoxy
- 2,3,4,4a - tetrahydro - (1H) - pyrido[1,2 - a]quinoline.
Example 27
dl-6-Carboxymethyl-7,9-dimethoxy-2,3,4,4a,5,6-hexahydro- 1H-pyrido[1,2-a]quinoline
[0132] In a flask equipped with magnetic stirrer, condenser and nitrogen inlet was placed
986 mg. (2.97 mole) dl - 6 - ethoxycarbonylmethylene - 7,9 - dimethoxy - 1,2,3,4,4a,5
- hexahydropyrido[1,2 - a]quinoline and 130 ml. absolute methanol. The mixture was
warmed to 40°C., then 74 ml. 1 N sodium hydroxide was added dropwise, the temperature
was increased to 45-50°C and 1.39 g. Raney alloy was added in portions. The resulting
mixture was stirred 70 minutes, allowed to cool, filtered and the filtrate evaporated.
The liquid residue was partitioned between water and chloroform, acidified to pH 5
with 1 N hydrochloric acid, shaken and the layers separated. The aqueous layer was
reextracted with chloroform and the combined organic phase washed with brine and dried
(MgS0
4). The solvent was evaporated to obtain 826 mg. of crude product. Mass spectrum (m/e):
305 (M
+), 246 (M―CH
2COOH).
Example 28
[0133]

[0134] In a flask fitted with magnetic stirrer and dry ice condenser was placed 826 mg.
dl - 6 - carboxymethyl - 7,9 - dimethoxy - 2,3,4,4a,5,6 - hexahydro - (1H) - pyrido[1,2
- a]quinoline, 50 ml. glacial acetic acid and 50 mi. 48% hydrobromic acid. The flask
was heated at 100°C. for 24 hours and the reaction mixture evaporated. The residue
was diluted with water, adjusted to pH 6-7 with 6N sodium hydroxide, the mixture saturated
with sodium chloride and extracted with ethyl acetate. The extracts were dried (Na
2S0
4) and solvent evaporated in vacuo to provide the crude title compound as an oily foam,
702 mg. This was purified by chromatography on a column of silica gel, eluting with
chloroform/ethyl ether. The product-containing fractions were combined and evaporated
to yield 390 mg. Mass spectrum (m/e): 259 (M
+),
1H―NMR (CDCI
3) ppm (delta): 1―4 (m, 15H, aliphatic and OH), 6.0 (m, 2H, aromatic).
Example 29
Lactone of dl-6-Carboxymethyl-7-hydroxy-9-(5-phenyl-2-pentyloxy)-2,3,4,4a,5,6-hexahydro[1H]pyrido[1,2-a]quinoline
[0135]

[0136] In a flame dried flask equipped with magnetic stirrer, condenser and nitrogen inlet
capillary was placed a solution of 390 mg. (1.5 mmole) dl - 6 - carboxymethyl - 7,9
- dihydroxy - 2,3,4,4a,5,6 - hexahydro(1H)-pyrido(1,2 - a]quinoline lactone in 3 ml.
dimethylformamide followed by 500 mg. (3.62 mmole) powdered potassium carbonate. The
resulting mixture was heated at 70°C. for 30 minutes, a solution of 452 mg. (1.95
mmole) dl - 5 - phenyl - 2 - methylsulfonyloxypentane in 2 ml. dimethylformamide was
added and the mixture was heated at 80°C. for 3.5 hours. An additional 135 mg. of
d/ - 5 - phenyl - 2 - methylsulfonyloxypentane in one ml. DMF was added and heating
at 80°C. continued for a further 1.8 hours. The reaction mixture was allowed to cool
and stirred at room temperature overnight. The mixture was again heated to 80°C.,
250 mg. of potassium carbonate (powder) was added, and the mixture held at 80°C. for
4 hours. Another increment (135 mg.) of d/ - 5 - phenyl - 2 - methylsulfonyloxypentane
in 1 ml. DMF was added, heating continued for one hour and the mixture again stirred
overnight at room temperature. The mixture was combined with water, extracted with
ethyl acetate and the combined extracts washed with water, brine and dried (MgS0
4). Evaporation of solvent in vacuo afforded a brown oil which was purified by chromatography
on a silica gel column (50 g., 70-230 mesh) packed with chloroform and eluted with
the same solvent. The product-containing fractions were combined and rechromatographed,
eluting with isopropyl ether/hexane, 2:1 to provide 263 mg. of the desired product.
The 'H-NMR spectrum was consistent with the structure of the title compound: 1.30
(d, 3H), 4.15 (m, 1H), 5.95-6.25 (m, 2H, aromatic), 7.20 (s, 2H, phenyl), peaks, ppm
(delta).
Example 30
dl-6-(2-Hydroxyethyl)-7-hydroxy-9-(5-phenyl-2-pentyloxy)-2,3,4,4a,5,6-hexahydro(1H)pyrido[1,2-a]quinoline
and Diacetate
[0137] A. Under a nitrogen atmosphere and anhydrous conditions, to a solution of 263 mg.
(0.65 mmole) the lactone of d/ - 6 - carboxymethyl - 7 - hydroxy - 9 - (5 - phenyl
- 2 - pentyloxy) - 2,3,4,4a,5,6 - hexahydro(1H)pyrido[1,2 - a]quinoline in 20 ml.
tetrahydrofuran (THF) was added in portions over three minutes, 25 mg. (0.66 mmole)
lithium aluminum hydride. The resulting mixture was stirred at ambient temperature
overnight. The reaction was quenched by addition of water, the pH adjusted to 6.0
with 1 N hydrochloric acid and the mixture partitioned between water and ethyl acetate.
The combined organic layers were washed with brine, dried (MgS0
4) and evaporated to dryness to provide 275 mg. of the desired dihydroxy compound as
an oil.
[0138] B. The product of Part A, 266 mg. (0.65 mmole) was dissolved in 10 ml. methylene
chloride and 1.8 ml. pyridine. To this was added 0.6 ml. acetic anhydride and the
mixture was stirred under nitrogen at room temperature for 48 hours. The reaction
mixture was concentrated in vacuo, the residue dissolved in ethyl acetate, washed
with water, brine and dried (MgS0
4). Evaporation of solvent gave 317 mg. of crude product. This was purified by chromatography
on 50 g. silica gel (70-230 mesh), eluting with chloroform. Fractions 3―8 were combined
and evaporated to dryness to yield 215 mg. of the purified diacetate. 'H-NMR (CDCI
3) ppm (delta): 1.30 (d, 3H), 2.05 (s, 3H, acetate), 2.30 (s, 3H, phenolic acetate),
6.05 (d, 1H), 6.20 (broad singlet, 1H), 7.20 (s, 5H); mass spectrum (m/e): 493 (M
+), 406 (M-CH
2CH
20COCH
3).
[0139] C. To 10 mi. methanol was added 0.79 ml. 1N sodium hydroxide solution and 187 mg.
(0.38 mmole) of the diacetate obtained in Part B, above. The reaction mixture was
stirred under nitrogen, in the dark for two hours. The mixture was neutralized with
1 N hydrochloric acid, evaporated to dryness, the residue taken up in ethyl ether,
washed with water and dried (MgS0
4). Evaporation of ether gave 148 mg. of dihydroxy compound. Mass spectrum (m/e): 409
(M
+), 364 (M―CH
2CH
2OH).
1H―NMR (CDCI
3) ppm (delta): 1.30 (d, 3H), 5.90 (s, 2H, aromatic), 7.20 (s, 5H, phenyl).
Example 31
3,5-Di methoxy-beta-N itrostyrene
[0140] A solution of 34.5 g. (0.208 mole) 3,5-dimethoxybenzaldehyde and 12.68 g. (0.208
mole) nitromethane in 40 mi. methanol was cooled to 0°C. under a nitrogen atmosphere.
To this was added dropwise a cold solution of 8.43 g. (0.211 mole) sodium hydroxide
in 30mi. water and stirring continued at 0°C. for 15 minutes after the addition was
completed. The mixture was diluted with ice-water and added slowly to a solution of
40 ml. concentrated hydrochloric acid in 60 ml. water. The precipitated product (44
g.) was collected by filtration and recrystallized from methanol to give 28.6 g.,
M.P. 132°C. J. Org. Chem., 27, 376 (1976) reported M.P. 133.5-134.5°C.
Example 32
4-(3,5-Dimethoxyphenyl)-5-Nitrocyclohexene
[0141] A stainless steel pressure'vessel was charged with 28.6 g. (0.137 mole) 3,5-dimethoxy-beta-nitrostyrene,
20 g. (0.378 mole) butadiene, 40 mi. toluene and a few crystals of hydroquinone. The
vessel was cooled to-78°C. under a nitrogen atmosphere and seaJed. The sealed vessel
was heated at 100°C. for 48 hours, cooled and the reaction mixture concentrated under
nitrogen. The residual solid was crystallized from methanol to afford 29.8 g. of title
compound, M.P. 80.5-82°C. J. Org. Chem., 27 376 (1962) reported M.P. 73―75°C.
1H―NMR (CDCl
3) ppm (delta): 3.75 (s, 6H, OCH
3), 4.95 (m, 1H, CHNO
2), 5.75 (s, 2H, olefin), 6.40 (s, 3H, aromatic).
Example 33
2-(3,5-Dimethoxyphenyl)-4-Cyclohexen-1-one
[0142] This product was obtained from 28.7 g. (0.109 mole) 4-(3,5-dimethoxyphenyl)-5-nitrocyclohexene
in the Nef reaction using the procedure of Wildman, J. Org. Chem., 17, 588 (1952)
for preparing 6-phenyl-3-cyclohexen-1-ones. After recrystallization of the crude product
from isopropanol/ethyl ether, 23.6 g. of the title compound was obtained, M.P. 60―62°C.,
lit. [J. Org. Chem. 27, 376 (1962)], M.P. 65.5-66.6°C.
Example 34
2-(3,5-Dimethoxyphenyl)Cyclohexanone
[0143] A mixture of 23.6 g. 2-(3,5-dimethoxyphenyl)-4-cyclohexen-1-one, 300 ml. ethanol
and 3 g. 10% Pd/C catalyst was hydrogenated at 40 psi (2.8 bar). After hydrogen uptake
ceased, the mixture was filtered, the filtrate evaporated in vacuo and the residue
recrystallized from isopropyl ether to obtain 17 g. of product, M.P. 61-62°C., lit
[J. Org. Chem., 27 376 (1962)], M.P. 62.5―63°C.
Example 35
2-(3,5-Dimethoxyphenyl)-1-(Methoxycarbonylmethylene)Cyclohexane
[0144] To a suspension of 3.9 g. (0.081 mole) 50% sodium hydride in 500 ml. anhydrous tetrahydrofuran
(THF) was added dropwise at room temperature a solution of 16.2 g. (0.089 mole) trimethylphosphonoacetate
in 50 ml. THF and the mixture stirred for 15 minutes. A solution of 17.4 g. (0.074
mole) 2-(3,5-dimethoxyphenyl)cyclohexanone in 100 ml. THF was added in portions after
which the mixture was heated at 70°C. for three hours and cooled to 0°C. Glacial acetic
acid, 5.4 g., was added and the resulting mixture diluted with water and extracted
with ethyl acetate. The extracts were dried (Na
2S0
4) and evaporated to give 22 g. of crude product which was crystallized from isopropyl
ether; 20.4 g., M.P. 80―81°C.
1H―NMR (CDCI
3) ppm (delta): 3.60 (s, 3H, COOCH
3), 3.80 (s, 6H, OCH
3), 5.20 (s, 1H, olefin), 6.34 (s, 3H, aromatic). Mass spectrum, exact mass for C
17H
24O
4: 292.3783. Found: 292.1658.
Example 36
2-(3,5-Dimethoxyphenyl)-1-(Carboxymethylene)Cyclohexane
[0145] To a solution of 20 g. of the above methyl ester in 100 ml. methanol, 50 ml. water
and 50 ml. tetrahydrofuran was added 42 ml. 5N sodium hydroxide and the mixture heated
on the steam-bath for three hours. After dilution with ice-water, 220 ml. 1N hydrochloric
acid was added, the mixture extracted with ethyl acetate, the extracts dried (Na
2S0
4) and evaporated in vacuo to give 20 g. of crude acid. Recrystallization from methylene
chloride/ethyl ether yielded 16.7 g. of product, M.P. 154―156°C. Mass spectrum, exact
mass for C
16H
22O
4: 278.3515. Found: 278.1526.
[0146] 1H―NMR (CDCI
3) ppm (delta): 3.70 (s, 6H), 5.15 (s, 1H), 6.30 (s, 3H), 10.90 (s, 1H, COOH).
Example 37
dl-trans-2-[2-(3,5-Dimethoxyphenyl)cyclohexyl)]Acetic Acid
[0147] To a solution of 15 g. (0.054 mole) 2 - (3,5 - dimethoxyphenyl - 1 - carboxymethylene
- 1 - (carboxymethylene)cyclohexane in 200ml. tetrahydrofuran and one liter of liquid
ammonia at -33°C. was added 832 mg. (0.119 mole) lithium metal. After a blue color
formed and persisted for two minutes, the reaction was quenched by addition of 15
g. ammonium chloride. The ammonia was evaporated under a stream of nitrogen. Water
(200 ml.) was added and the solution acidified to pH 3.5 with 6N hydrochloric acid.
The aqueous layer was extracted with methylene chloride, the extracts dried (Na
2S0
4) and evaporated to give 15 g. of crude product. This was triturated with hexane and
filtered to afford 14.8 g. of product, M.P. 110―111.5°C.
1H―NMR (CDCI
3) ppm (delta) 270 MHz: 1.90 (d, 1H, J=14.6Hz), 2.16 (dd, 2H, J=14.7, 2.3), 2.17 (td,
1H, J=11, 3).
[0148] From the above NMR data the relative stereochemical structure below, was assigned.

. Example 38
dl-4a,10b-trans-7,9-Dimethoxy-2,3,4,4a,5,10b-Hexahydro-1H-Phenanthren-6-one
[0149] To a solution of 14.7 g. (0.052 mole) trans - 2 - [2 - (3,5 - dimethoxyphenyl)cyclohexyl]acetic
acid, obtained above, in 28m1. trifluoroacetic acid at 0°C. was added 20 mi. trifluoroacetic
anhydride and the mixture stirred at 0°C. for 15 minutes. The volatiles were evaporated,
the residue taken up in methylene chloride, washed in turn with water, sodium bicarbonate
solution, brine and dried over anhydrous sodium sulfate. Evaporation of solvent gave
15.7 g. of crude product which was recrystallized from ethyl ether to afford 12.5
g. of title compound, M.P. 110-111°C. Mass spectrum, exact mass calculated for C
16H
20O
3: 260.3358 Found: 260.1404.
Example 39
d/-4a,10b-trans-7,9-Dihydroxy-2,3,4,4a,5,10b-hexahydro-1 H-phenanthren-6-one
[0150] A solution of 12.3 g. (0.047 mole) dl - 4a,10b - trans - 7,9 - dimethoxy - 2,3,4,4a,5,10b
- hexahydro - 1H - phenanthrene - 6 - one in 220 ml. glacial acetic acid and 220 ml.
48% hydrobromic acid was heated under a nitrogen atmosphere for 36 hours at 100°C.
The volatiles were evaporated under reduced pressure and the residue purified by chromatography
on silica gel, eluting with ethyl acetate to give 12 g. of product, M.P. 189―200°C.
Recrystallization from ethyl acetate/chloroform gave 10 g. of pure product, M.P. 200-201°C.
1H―NMR (CD
3COCD
3) ppm (delta): 6.50-6.10 (m, 2H, aromatic), 13.0 (s, 1H, OH). Mass spectrum, exact
mass calculated for C
14H
16O
3( 232.2816 Found: 232.1097.
Example 40
dl-4a,10b-trans-7-Hydroxy-9-(5-phenyl-2-pentyloxy)-2,3,4,4a,5,10b-hexahydro-1H-phenanthren-6-one
[0151] A mixture of 9.9 g. (0.043 mole) dl-trans - 7,9 - dihydroxy - 2,3,4,4a,5,10b hexahydro
- 1 H - phenanthren - 6 - one, 7.1 g. (0.103 mole) potassium carbonate and 120 ml.
dimethylformamide (DMF) was heated at 70°C. for thirty minutes. A solution of 13.55
g. (0.056 mole) 2-methylsulfonyloxy-5-phenyl-pentane in 10 ml. DMF was added in one
portion and the mixture heated under nitrogen at 80°C. overnight. The reaction mixture
was diluted with ice-water, extracted with ethyl acetate, the extracts dried (Na
2S0
4) and evaporated in vacuo to give 21 g. of crude product. Column chromatography on
750 g. silica gel, eluting first with chloroform/hexane, then chloroform alone and
finally with chloroform/ethyl ether, gave 14 g. of product as an oil.
1H-NMR (CDCl
3) ppm (delta): 1.40 (d, 3H), 4.45 (m, 1H), 6.20―6.50 (m, 2H), 7.30 (s, 5H), 13.10
(s, 1H).
Example 41
dl-4a,10b-trans-7-Benzyloxy-9-(5-phenyl-2-pentyloxy)-2,3,4,4a,5,10b-hexahydro-1H-phenanthren-6-one
[0152] To a suspension of 720 mg. (0.015 mole) of a 50% oil dispersion of sodium hydride
in 25 ml. dimethylformamide (DMF) at 0°C. was added dropwise a solution of 5.0 g.
(0.013 mole) dl - trans - 7 - hydroxy - 9 - (5 - phenyl - 2 - pentyloxy) - 2,3,4,4a,5,10b
- hexahydro - 1 H - phenanthrene - 6 - one in 15 ml. DMF and the mixture allowed to
warm to room temperature. To this was added in one portion 2.56 g. (0.015 mole) benzyl
bromide and the mixture stirred under nitrogen for 18 hours at room temperature. Water
was added to dilute the mixture, which was then extracted with ethyl acetate. The
extracts were dried (Na
2S0
4) and solvent evaporated to give 7 g. of crude product which was purified by chromatography
on silica gel, eluting with ethyl ether/hexane. Evaporation of the product-containing
fractions gave 5.8 g. 'H-NMR (CDCl
3) ppm (delta): 1.10 (d, 3H), 5.10 (s, 2H), 6.23-6.54 (m, 2H), 6.95-7.70 (m, 10H).
Example 42
dl-4a,10b-trans-7-Benzyloxy-6-hydroxy-6-ethoxycarbonylmethyl-9-(5-phenyl-2-pentyloxy)-2,3,4,4a,5,10b-hexahydro-1
H-phenanthrene
[0153] To a solution of 4.07 g. (0.0403 mole) diisopropylamine in 100 ml. tetrahydrofuran
(THF) at 0°C. was added dropwise a solution of 16.8 ml. (0.0403 mole) 2.4M n-butyllithium
in hexane and the mixture stirred under a nitrogen atmosphere for one hour, then cooled
to -78°C. A mixture of 3.55 g. (0.0403 mole) ethyl acetate in 10 ml. THF was added
dropwise, stirring continued for 30 minutes at -78°C., then 5.8 g. (0.0124 mole) dl
- trans - 7 - benzyloxy - 9 - (5 - phenyl - 2 - pentyloxy) - 2,3,4,4a,5,10b - hexahydro
- 1 H - phenanthrene -6 - one dissolved in 20ml. THF was added dropwise and the resulting
mixture stirred for 10 minutes. Glacial acetic acid (2.5 g.) was added and extracted
with ethyl acetate. The extracts were dried (Na
2SO
4) and the solvent evaporated in vacuo to give 6.9 g. of product which was used without
further. purification.
1H―NMR (CDCl
3) ppm (delta): 4.105 (q, 2H), 4.605 (s, 1H, OH), 5.055 (S, 2H, CH
2C
6H
5).
Example 43
dl-4a,10b-trans-7-Acetoxy-6-Ethoxycarbonylmethylene-9-(5-phenyl-2-pentyloxy)-2,3,4,4a,5,10b-hexahydro-1
H-phenanthrene
[0154] A mixture of 6.9 g. dl - trans - 7 - benzyloxy - 6 - hydroxy - 6 - ethoxycarbonylmethyl
- 9 - (5 - phenyl - 2 - pentyloxy) - 2,3,4,4a,5,10b - hexahydro - 1H - phenanthrene,
250 ml. ethanol and 3.g. 5% Pd/ C catalyst was hydrogenated at 40 psi (2.8 bar). Removal'of
catalyst by filtration and evaporation of the filtrate gave 5.7 g. of residue. This
was taken up in 100 mi. methylene chloride, 4.5 g. acetic anhydride and 8.0 g. triethylamine
added and the mixture allowed to stand overnight. The volatiles were evaporated in
vacuo, the residue dissolved in ethyl acetate, washed with water, dried (Na
2S0
4) and the solvent evaporated to give 5.6 g. of product which was used without purification.
Example 44
d/-4a,10b-trans-7-Hydroxy-6-Carboxymethylene-9-(5-phenyl-2-pentyloxy)-2,3,4,4a,5,10b-hexahydro-lH-phenanthrene
lactone,
[0155]

[0156] A. To a solution of 5.6 g. (0.011 mole) d/ - trans - 7 - acetoxy - 6 - ethoxycarbonylmethylene
- 9 - (5 - phenyl - 2 - pentyloxy) - 2,3,4,4a,5,10b - hexahydro - 1H - phenanthrene
in 75 ml. tetrahydrofuran and 25 mi. methanol was added 56 ml. 1 N sodium hydroxide
and the mixture stirred at room temperature for one hour. Then 56 mi. 1 N hydrochloric
acid was added, the mixture extracted with ethyl acetate and the extracts dried over
anhydrous sodium sulfate. Evaporation of solvent gave 5 g. of crude product which
was, purified by chromatography on 400 g. silica gel eluting with ethyl ether/hexane.
Fractions containing like product were combined and evaporated to dryness to obtain
1.44 g. of a less polar product and 2.2 g. of the more polar title compound. Infrared
spectrum (CHCI
3): 1710 cm-'. Mass spectrum, exact mass, calculated for C
27H
30O
3: 402.538. Found: 402.218.
[0157] B. The less polar product was identified as the corresponding saturated lactone.
Infrared spectrum (CHCI
3): 1725 cm-
1. Mass spectrum, exact mass, calculated for C
27H
32O
3: 404.554 Found: 404.239.
[0158] Alternatively, the saturated lactone is prepared from the 6,8-dimethoxy-9-one compound
provided in Example 38 by sequential operation of the procedures of Examples 25 through
29.
Example 45
dl-4a,10b-trans-7-Hydroxy-6-beta-(2-Hydroxyethyl)-9-(5-phenyl-2-pentyloxy)-1,2,3,4,4a,5,6,10b-octahydrophenanthrene
[0159] A solution of dl - 4a,10b - trans - 7 - hydroxy - 6 - carboxymethylene - 9 - (5 -
phenyl - 2 - pentyloxy) - 2,3,4,4a,5,10b - hexahydro - 1H - phenanthrene lactone (2.1
g., 5.2 mmole) in 100 mi. ethyl ether was added to 400ml. liquid ammonia. Lithium
metal (84 mg., 12 mmole) was added in portions and the blue color allowed to persist
for two minutes. The reaction was quenched with 2.1 g. ammonium chloride, the ammonia
evaporated under a stream of nitrogen, the residue taken up in water, acidified to
pH 3 with 1N hydrochloric acid and extracted with ethyl acetate. The extracts were
dried (Na
2S0
4) and evaporated in vacuo to give 2.1 g. of crude product which was purified by chromatography
on silica gel, eluting with isopropyl ether/hexane mixtures to afford 440 mg. of title
compound.
1H―NMR (CDCl
3) ppm (delta): 1.15 (d, 3H, CH
3), 3.80 (t, 2H, CH
2OH), 4.25 (m, 1 H, OCH), 6.25-6.50 (m, 2H, aromatic), 7.20 (s, 5H, phenyl).
Example 46
[0160]

[0161] A solution of 630 mg. (1.60 mmole) of the saturated lactone obtained in Example 45,
Part B, in 20ml. toluene was cooled to -78°C. and 1.6 ml. of 1N diisobutylaluminum
hydride (DIBAL-H) in hexane was added. The resulting mixture was stirred at -78°C.
for 15 minutes, methanol added to quench the reaction, the mixture poured into ethyl
ether and washed with 50% aqueous sodium potassium tartrate. The ether layer was dried
(MgS0
4) and the solvent evaporated to give 640 mg. of crude lactol which was used without
further purification.
Preparation 1
5-Phenyl-2-pentyl Mesylate .
[0162] To a stirred solution of 5-phenyl-2-pentanol (482 g.; 2.94 moles) in tetrahydrofuran
(2250 ml.) at 0°C was added methanesulfonyl chloride (300 ml.) at such a rate that
the'internal temperature does not rise above 10°C. (total addition time 4.5 hours).
After addition is complete, the reaction mixture was allowed to warm to room temperature
and stirring was continued for an additional hour. The reaction mixture was filtered
and the supernate concentrated to a light yellow oil (2800 g.) which was dissolved
in chloroform (2 liters) and washed with water (4 x 1 liter), brine (1 x 1 liter),
charcoal treated (50 g.), dried (MgS0
4), filtered through diatomaceous earth and concentrated to a light orange oil (687
g., 95% yield). This material was suitable for use without further purification.
[0163] 'H-NMR (CDCI
3): 7.23 (s, 5H, aromatic), 4.53-5.13 (m, 1H, ―CH―O―) 2.93 (s, 3H, O―SO
2―CH
3), 2.42-2.93 (m, 2H ―CH
2C
6H
5), 1.50-1.92 [m 4H, ―(CH
2)
2―], 1.23 (s, 3H, O―CH―CH) ppm.
Preparation 2
4-Phenyl-1-butyl Mesylate
[0164] By the method of Preparation 1, 4-phenyl-1-butanol was converted to title product,
a yellow oil; m/e 228; 'H-NMR (CDCI
3): 7.22 (bs, 5H, aromatic), 4.08-4.34 (m, 2H, ―CH
2―O―), 3.93 (s, 3H, S0
2CH
3), 2.40-2.82 (m, 2H, CH
2C
6H
5], 1.51-1.93 (m, 4H, ―CH
2CH
2―) ppm.
Preparation 3
d(+)-2-Octyl methylate and 1 (-)-2-Octyl mesylate
[0165] By the method of Preparation 1, the optically active forms of 2-octanol were converted
to:
1(-)-2-octyl mesylate, a colorless oil, [alpha]

= -9.695° (CHCI3, C=2.6),'H-NMR (CDCI3): 4.79 (bg, 1H, ―CH―O―), 2.97 (s, 3H, S-CH3), 1.40 (d, 3H, CH3-CH), 0.87 (t, 3H, CH2CH2), 1.0-2.0 [m, 10H, ―CH2)5―] ppm; and
d(+)-2-octyl mesylate, [alpha]

= +9.238° (CHCI3, C = 2.8), 1H―NMR identical to the 1(-) form.
Preparation 4
5-Phenyl-2S-pentyl Brucine Phthalate
[0166] Brucine (57.6 g., 0.146 mole) in 105 ml. of acetonitrile was added to the acetonitrile
solution of 5-phenyl-2-pentyl hydrogen phthalate and the mixture heated to 55-60°.
Maintaining this temperature, isopropyl ether (610 ml.) is added in a steady stream.
The solution is cooled gradually to 23°, and the crystalline material which begins
to form at 45-55°, granulated for 16 hours, recovered by filtration and air dried
at 55° (33 g.). Highly resolved material has [alpha]
DCHCl3 +40.0. If at this stage the rotation is less than +38.5°, it is recrystallized from
acetonitrile-isopropyl ether (for 33 g. of crude, 130 ml. of acetonitrile and 300
mi. of isopropyl ether was used, with recovery of 26 g. of purified title product).
Preparation 5
5-Phenyl-2S-pentanol
[0167] S-Brucine salt of the preceding Preparation (10.0 g., 14.2 mmoles) was combined with
125 ml. of toluene and 150 mi. of water. With stirring the pH was adjusted to 1.7
with about 6 ml. of 3N HCI. The aqueous layer was separated and extracted 2 x 40 ml,
toluene. Brucine was precipitated from the aqueous layer by adjusting the pH to 11.5
with 50% NaOH. Recrystallization from isopropyl alcohol provides material suitable
for reuse. The toluene layers were combined, back-washed with 75 ml. of water, concentrated
to 45―50 ml. Fresh water (65 ml.) and then KOH (85%, 1.90 g., 28.8 mmoles) were added
and the mixture stirred for 1 hour at room temperature and then 2 hours at 82―84°.
The reaction mixture was cooled to 25°, the toluene layer separated and the aqueous
layer washed 3 x 20 ml. toluene. The toluene layers were combined, washed 1 x 20 ml.
saturated NaCl, dried (MgS0
4), filtered and concentrated to yield title product as an oil (1.91 g.), purified
by distillation in vacuo (1.64 g., b.p. 85―92°/0.1 mm, [alpha]

+ 8.24 to +8.57°).
Preparation 6
5-Phenyl-2R-pentanol
[0168] To a solution of racemic 5-phenylpentan-2-ol (4.9 g., 0.03 mole) in 50 mi. toluene
was added d-mandelic acid (4.5 g., 0.03 mole) and a trace of p-toluenesulfonic acid.
This mixture was heated for 10 hours at reflux using a Dean Stark device to remove
water. Upon cooling, 50 mi. of benzene was added and the reaction washed with 3 x
100mi. of saturated NaHC0
3 solution, the organic phase dried (MgS0
4) and concentrated to yield 7.0 g. of a colorles oil (78%). A portion of this oil
(5.4 g.) was subjected to column chromatographic separation using 500 g. of silica
gel and an ethyl ether-hexane (1 to 4) solvent system. The separation of the diastereomeric
mandelates could conveniently be followed by
1H―NMR. The first eluting 5-phenyl-2R-pentanol had the CH
3 doublet (J = 7.0) centered at 1.05 ppm and the second eluting 5-phenyl-2S-pentanol
at 1.25 ppm. Using a fraction collector, 150 15 mi. fractions were collected from
the above column. Fractions 101-110 show an isomer ratio of ca. 95:5 of the first
eluting isomer (HPLC). These fractions were combined and concentrated to yield 0.90
g.; [alpha]
D≦
5 = 37.56°'(CHCI3
).
[0169] A portion of the purified first eluting isomer (0.80 g., 0.0027 mole) was dissolved
in 25 ml. of methanol and 2.0 mi. of H
20 and 0.50 g. of K
2C0
3 (0.0036 mole) was added and this reaction stirred for 24 hours at 25°.. Water (10
ml.) was then added and the reaction extracted with 2 x 25 ml. of EtOAc; the organic
layers combined, dried (MgS0
4) and concentrated to yield 0.40 g. (90%) of 5-phenylpentan-2-ol, [alpha]

= -7.16° (CHCI
3).
Preparation 7
Ethyl 2S-Benzyloxypropionate
[0170] Under nitrogen, benzyl methanesulfonate (181.5 g., 0.975 mole) was combined and stirred
with S-ethyl lactate (ethyl 2S-hydroxypropionate; 393 g., 3.33 moles) and the resulting
solution heated on a steam bath to 94°C. over 15 minutes and held for 1.5 hours at
this temperature. The reaction mixture was cooled to " 45°C., poured into 2 litres
of cold toluene. Water (500 ml.) was added and the mixture stirred for 5 minutes.
The aqueous phase was separated and extracted with 200 ml. fresh toluene. The organic
layers were combined, washed in sequence 2 x 500ml. H
20, 1 x 500 ml. saturated NaHC0
3, 2 x 500 ml. water and 1 x 500ml. saturated NaCI, dried over MgS0
4, filtered, and evaporated in vacuo to yield crude product as an oil [228 g., 112%
[alpha]

-60.8°, C = 1.11 (CHCl
3)], which
1H―NMR indicated to be contaminated with ethyl lactate. Distillation in vacuo gave,
after an early boiling solvent fraction 1 [25 ml., b.p. to 79°C./1.2 mm.; [alpha]
d -6.9°, C = 1.13 (CHCl
3)] fractions 2-8 [74 ml., b.p. 82°C./1.3 mm to 114°C./3 mm.; [Alpha]
D ― 42.1° to -76.2°, C = 1.09-1.16 (CHCl
3)] as a mixture of S-ethyl lactate and title product; and fractions 9―12 [57 mi.;
b.p. 115°C./3 mm., 98―100°/0.75 mm., 102-106°C./1.0 mm.; [alpha]
D -80.0° to -83.7°, C = 1.01-1.17 (CHCl
3)] of substantially pure title product. A higher boiling pot residue of 49 g. remained.
A portion of fraction 10 (3 g.) was voided of traces of ethyl lactate by taking up
in 100 ml. of hexane and equilibrating with 30 ml. H
20. The hexane layer was separated, washed 3 x 30 ml. H
20, dried over MgSO
4, filtered and concentrated to an oil [2.4 g.; R, 0.32 (6:1 hexane: ethyl acetate);
[alpha]

- 83.3°, C = 1.13 (CHCl
3)].
Preparation 8
2S-Benzyloxy-1-propanol
[0171] Fractions 2-9 and 12 from the above distillation (106.1 g. total weight. 0.45 moles
of ethyl 2S-benzyloxypropionate and 0.25 moles of S ethyl lactate) was dissolved in
100ml. of anhydrous ethanol and the solution added dropwise to a stirred mixture of
NaBH
4 (37.85 g., 1.0 mole) and 500 ml. of anhydrous ethanol under nitrogen over a one hour
period. The temperature was maintained at 25-30°C. during addition by cooling with
a 20°C. water bath. After stirring for 20 hours at ambient temperature, the reaction
mixture was cooled to 10°C. and 95 mi. of 12N HCI (1.14 mole) added dropwise over
15 minutes under a sweep of nitrogen. The resulting slurry was filtered with 100 ml.
ethanol wash. The filtrate and wash were combined and concentrated in vacuo to 150
ml. The concentrate was diluted with 200 ml. of water and 300 ml. of ethyl acetate,
the pH was adjusted from 1.5 to 9.0 with 50 ml. of 4N NaOH (causing precipitated solids
to dissolve) and the layers were separated. The aqueous phase was washed 1 x 100 ml.
and then 1 x 50 ml. of ethyl acetate. The three organic layers were combined, washed
2 x 150 ml. H
20 and then 1 x 150 ml. saturated NaCI, dried over MgS0
4, filtered, and evaporated to yield title product as an oil [50.5 g.; [alpha]

+47.9, C = 1.08 (CHCI
3); + 27.736 (neat); R, 0.1 (CH
2Cl
2)].
Preparation 9
2S-Benzyloxy-1-propyl Mesylate
[0172] Under nitrogen, 2S-benzyloxy-1-propanol (49.8 g., 0.3 mole), 400 mi. of CH
2CI
2 and triethylamine (40.5 g., 0.4 mole) were combined, stirred and cooled to -5°C.
in an ice-water-acetone bath. Maintaining -5°C., methanesulfonyl chloride (37.8 g.,
0.33 mole) in 30 ml. CH
2CI
2 was added over one hour. After stirring at -5°C. for 0.5 hour, H
20 (200 ml. at 5°C.) was added. The layers were separated and the aqueous layer washed
1 x 100 ml. CH
2CI
2. The combined organic layers were washed in sequence 1 x 100 ml. H
20, 1 x 100 ml. H
20, 1 x 100 ml. 1 N HCI, 1 x 100 ml. H
20, 1 x 100 ml. saturated NaHC0
3 and 1 x 100 ml. H
20, dried over MgS0
4, filtered, and concentrated in vacuo to yield title product as an oil [72.2 g., 98.5%;
[alpha]

+ 7.7, C = 1.00 (CHCI
3); R, 0.6 (CH
2Cl
2)].
Preparation 10
2S-Benzyloxy-1-propyl lodide
[0173] Under nitrogen with stirring, sodium iodide (90 g., 0.6 mole) was dissolved in one
liter dry acetone. At 32°C., 2S-benzyloxy-1-propyl mesylate (71.5 g., 0.293 mole)
was added. The reaction mixture was warmed to 59-60°C. (gentle reflux) and held for
20 hours, at which time tic indicated about 20% starting material to remain. Additional
sodium iodide (30 g., 0.2 mole) was added and refluxing continued for 3 hours. The
reaction was cooled to room temperature and filtered with acetone wash. The combined
filtrate and wash was concentrated to 150ml. of oily solids, diluted with 300 ml.
toluene and 200ml. H
20, the layers separated and the aqueous phase extracted 2 x 100 ml. toluene. The three
organic layers were combined, washed 2 x 200 ml. H
20, dried over MgS0
4, filtered and evaporated to yield title product as an oil [79 g., 96%; [alpha]
D = +8.0°, C = 1.08 (CHCl
3),
1H-NMR (CDCl
3) delta (ppm): 1.4 (d, 3H), 3―3.6 (m, 3H), 4.6 (s, 2H), 7.35 (s, 5H)].
Preparation 11
Ethyl 2-Benzoyl-4S-benzyloxyvalerate
[0174] Under nitrogen, sodium hydride (50% in oil, 13.6 g., 0.283 mole) was washed with
3 x 200 mi. of dry hexane. To the resulting hexane wet NaH, 130 ml. dimethylformamide
was added, followed by the dropwise addition of ethyl benzoylacetate (54.4 g., 0.283
mole) over 45 minutes, maintaining the temperature 28―32°C. with a 10°C. water bath
and sweeping away evolved H
2 with N
2. After stirring for 85 minutes at 25°C., 2S-benzyloxy-1-propyl iodide (78 g., 0.283
mole) was added with 40ml. of dimethylformamide for rinse. The reaction mixture was
then heated and stirred at 122-126°C. for 2 hours (during which solids precipitated),
cooled to 70°C., diluted with 350 mi. toluene and 560 ml. of ice water, and the resulting
layers separated. The aqueous layer was extracted 3 x 150 mi. toluene. The four organic
layers were combined, washed 3 x 150 ml. H
20 and then 1 x 150 ml. saturated NaCl, dried over MgS0
4, filtered and concentrated in vacuo to yield title product as an oiJ (90 g., 94%;
[alpha]

+15.8°, C = 1.12 (CHCI
3); R
f 0.35 (6:1 hexane:ethyl acetate)].
Preparation 12
4S-Benzyloxy-1-phenyl-1-pentanone
[0175] Ethyl 2-benzoyl-4S-benzyloxyvalerate (89 g., 0.26 mole), ethanol (175 ml.), water
(175 ml.) and KOH (85%, 51. g., 0.8 mole) were combined with stirring under nitrogen,
during which the temperature rose to 45°C. The reaction mixture was heated to 79°C.
under a reflux condenser and held for 18 hours. The reaction mixture was cooled to
25°C., diluted with 350 ml. of water and 300 ml. of toluene, the layers separated,
and the aqueous layer washed 1 x 200ml. and 2 x 150 ml. toluene. The organic layers
were combined, washed 2 x 200 ml. H
20 and 1 x 200 ml. saturated NaCl, dried over MgS0
4, filtered and concentrated in vacuo to yield title product as an oil [45.5 g., 65%;
[alpha]

+21.92°d, C = 1.20 (CHCI
3); R, 0.55 (6:1 hexane:ethyl acetate)].
Preparation 13
5-Phenyl-2S-pentanol
[0176] 4S-Benzyloxy-1-phenyl-1-pentanone (45 g., 0.168 mole) in 150 ml. of toluene, 15ml.
of absolute alcohol and 3 drops concentrated HCI were hydrogenated over 4 g. 50% water
wet 5% Pd/C at 50-60 psig (3.5-4.2 bar) and 25°C. After hydrogenating for 6 hours,
an additional 4 g. catalyst was charged and hydrogenation continued for 2.5 hours,
by which time three equivalents of hydrogen were consumed and there had been no uptake
over the final 1.5 hour period. The catalyst was recovered by filtration. The filtrate
was neutralized by stirring over a 5 cc volume of solid NaHCO
3, dried over MgS0
4, filtered and concentrated in. vacuo to yield title product as an oil [22 g., 80%;
[alpha]

+8.63, C = 1.02 (CHCI
3); R
f 0.2 (6:1 hexane:ethyl acetate)]. If desired the title product was further purified
by simple distillation to remove traces of tlc origin material, b.p. 90-94/0.7 mm.
with nearly quantitative recovery.